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This Month's Featured Story
For the September story, we're featuring two minerals in a head-to-head shoot-out of chemistry and qualities. Once again, these two minerals are named very similarly, but are quite different.
So what's its gonna be?
Rhodonite vs Rhodochrosite!
While these two minerals are related in many ways, they are from two completely different families of minerals. Here is how they breakdown.
Formula CaMn3Mn[Si5O15] - Inosilicates Family
Rarely found as tabular red crystals, usually in clusters with the crystals growing parallel to one another, or nearly so. Also as pink masses with other metallic minerals.
Named after the greek word for rose.
Comes in around 6 on the Mols hardness scale.
Formula MnCO3 - Calcite Family
Typically found in rhombic (square-ish) crystals or as stalactites, kind of like calcite often forms. Polished and tumbled stones can resemble rose quartz.
It is also named from the greek for rose coloring.
Comes in at about 3.5 on the Mols hardness scale.
Large translucent red Rhodochrosite crystals are rare and highly sought after by collectors.
Rhodonite is a pink manganese silicate mineral of variable composition that often contains significant amounts of iron, magnesium, and calcium. It has a generalized chemical composition of (Mn,Fe,Mg,Ca)SiO3. Rhodonite is often associated with black manganese oxides which may occur as dendrites, fracture-fillings, or matrix within the specimen. Other names for rhodonite include "manganese spar" and "manganolite." Rhodonite is an uncommon mineral. It is found in a few small deposits across the world.
Rhodochrosite is a manganese carbonate mineral that ranges in color from light pink to bright red. It is found in a small number of locations worldwide where other manganese minerals are usually present. Rhodochrosite is sometimes used as an ore of manganese but is rarely found in economic quantities. Specimens with a wonderful pink color are used to produce highly desirable gemstones. Rhodochrosite is rarely found as well-formed crystals, so crystals can be extremely valuable as mineral specimens.
Pink & White - Rhodochrosite!
Red Rhodochrosite Dogtooth Crystal
Rhodochrosite stalactite slab cross-section
Pink & Black - Rhodonite!
This month's article is going to be a bit different. Instead of featuring one mineral or fossil, were going to have a skirmish. A head-to-head contest between two minerals who happen to have names that are soooo similar that even mineral collectors will pause and have to think about what it is that we're talking about. We plan to do this a few more times in the hopes of making it fun and provide some learning about the mineral world as well.
So what's its gonna be?
Baryte vs Beryl!
While these two minerals are related in some ways, they are from two completely different families of minerals, and to add to the confusion, one often gets spelled differently too. Now for the breakdown.
Formula BaSO4 - Sulfate Family
Typically found as thick to thin tabular crystals, usually in clusters with the crystals growing parallel to one another, or nearly so. Also as bladed, white masses or flowery like clusters of crystals.
Named for its heaviness as a non-metallic mineral.
Comes in at a 3 on the Mols hardness scale.
Baryte is often written as Barite and it's fairly soft for a mineral. Too soft to make gemstones out of, but it can be very pretty forming transparent blue, yellow, and clear crystals. The mineral baryte is mined as a source of Barium and is used in many industrial products and processes. Many mineral collectors will have a few pieces in their collection for their interesting shape, colors and it's not too expensive for some really interesting pieces.
Formula Be3Al2(Si6O18) - Cyclosilicates Family
Typically found in hexagonal columnar crystals.
Its name is so old that we guess it came from the greek "beryllos" which referred to a number of blue-green stones in antiquity.
Comes in at a 7.5 to 8 on the Mols hardness scale.
Beryls are known by different names based on their color, like green for emerald.
Beryl is known for its stunning rainbow of colors. It is prized as a gemstone in jewelry. Prized beryls come in red (Bixbite), green (Emerald), light blue (Aquamarine), yellow (Heliodor), purple-blue (Maxixe), pink (Morganite), and colorless (Goshenite). Many people favor Beryls over diamonds and rubies as their favorite gemstone. Large and tall beryl crystals of clean, bright colors are highly prized by collectors and gemologists.
The Colors of Beryl
The Biggest Bug ever!
The Prehistoric Dragonfly with a Two-foot Wingspan
Image Credit: Fossil of Meganeuridae
The largest known insect of all time was a predator resembling a dragonfly but was only distantly related to them. Its name is Meganeuropsis permiana, and it ruled the skies before pterosaurs, birds, and bats had even evolved.
Most popular textbooks make mention of “giant dragonflies” that lived during the days before the dinosaurs. This is only partly true, for real dragonflies had still not evolved back then. Rather than being true dragonflies, they were the more primitive ‘griffin flies’ or Meganisopterans. Their fossil record is quite short. They lasted from the Late Carboniferous to the Late Permian, roughly 317 to 247 million years ago.
Meganisoptera is an extinct family of insects, all large and predatory and superficially like today’s odonatans, the dragonflies, and damselflies. And the very largest of these was Meganeuropsis. It is known from two species, with the type species being the immense M.permiana. Meganeuropsis permiana, as its name suggests is from the Early Permian timeframe.
The fossils of Meganeura were first discovered in France in the year 1880. Then, in 1885, the fossil was described and assigned its name by Charles Brongniart who was a French Paleontologist. Later in 1979, another fine fossil specimen was discovered at Bolsover in Derbyshire.
There has been some controversy as to how insects of the Carboniferous period were able to grow so large.
Some leading Ideas are that oxygen levels and atmospheric density were different during the early Permian.
The way oxygen is diffused through the insect's body via its tracheal breathing system puts an upper limit on body size, which prehistoric insects seem to have well exceeded. It was originally proposed that Meganeura was able to fly only because the atmosphere at that time contained about 15% more oxygen than the present 20%.
Another explanation for the large size of Meganeurids is comparing it to living predators is warranted. It was suggested in 2004 that the lack of aerial vertebrate predators allowed pterygote insects to evolve to maximum sizes during the Carboniferous and Permian periods, perhaps accelerated by an evolutionary "arms race" for an increase in body size between plant-feeding Palaeodictyoptera and Meganisoptera as their predators.
Another theory suggests that insects that developed in water before becoming terrestrial as adults grew bigger as a way to protect themselves against the high levels of oxygen. They grew in size simply because the ecosystem allowed them to, and the increased levels of oxygen have been shown to help today's insects grow larger when kept in an oxygen-rich atmosphere.
Though always associated with the modern-day dragonflies due to their appearance, considering the various structural and other characteristic differences between them, these insects were often classified as griffin flies.
It was one of the largest known insects that ever lived, with a reconstructed wing length of 330 millimeters (13 in), an estimated wingspan of up to 710 millimeters (28 in), and a body length from head to tail of almost 430 millimeters (17 in).
The term 'Meganeura' means large-veined, and these insects had similar vein patterns in their wings. However, the vein patterns found in the wings of dragonflies usually vary.
It is believed that their hunting and preying methods were quite similar to those of modern-day dragonflies. However, it may have attacked many more creatures because of its larger size.
Their wings had a network of veins. Moreover, they were heavily veined and had cross braces for strength unlike those of the present-day dragonflies that have delicate wings.
They believe that it was impossible for the massive bodies of these insects to survive in the present-day atmospheric conditions and that this may have led to their extinction. (The oxygen content in today's atmosphere is up to 21% and back in the Carboniferous period, it was up to 35%.)
The breathing mechanism of these insects allowed the passage of air through a system of tracheal tubes, transporting the oxygen directly to the internal tissues.
Today's Dragon Fly Larvae
Fossil of a Dragonfly Larvae
A New Russian Mineral Discovery that's More than a Pretty Face
A research team led by crystallographer (crystal specialist) Stanislav Filatov at St. Petersburg University found a colorful new entry into the world of minerals: petrovite. Petrovite is beautiful to look at, but it could also help inspire advancements in next-generation batteries.
The research team that found petrovite was headed by crystallography professor Stanislav Filatov, who studied the minerals of Kamchatka for over 40 years. The area offers amazing mineralogical diversity, with dozens of new minerals found there in recent years, according to the university's press release. Specifically, Filatov focused his attention on scoria (or cinder) cone volcanos and lava flows formed after the eruptions of the Tolbachik Volcano.
The bright blue mineral comes from a wild place: a volcanic landscape formed by major eruptions in the 1970s and the 2010s in the Kamchatka Peninsula of Russia. "This territory is unique in its mineralogical diversity. In recent years, researchers have discovered dozens of new minerals here, many of which are one-of-a-kind in the world," the university said in a statement on Tuesday.
The mineral is named for another St. Petersburg University crystallographer, Tomas Petrov. The team published a study on petrovite in the journal Mineralogical Magazine earlier this year.
Petrovite is particularly interesting because it's a rarity in its composition and structure. Petrovite is a blue-green mineral, with the chemical formula of Na10CaCu2(SO4)8. "The mineral consists of oxygen atoms, sodium sulphur and copper, which form a porous framework," the university states. "The voids are connected to each other by channels through which relatively small sodium atoms can move."
The scientists think its structure of voids connected by channels, which can pass through small sodium atoms, holds potential for ionic conductivity. The mineral may be adaptable as cathode material in sodium-ion batteries. Due to the abundance of salt, sodium-ion batteries could be a very inexpensive alternative to lithium-ion batteries you can commonly find in many devices today.
Besides researchers from St. Petersburg University, other Russian scientists involved came from the Institute of Volcanology and Seismology of the Far Eastern Branch of the Russian Academy of Sciences, and the Grebenshchikov Institute of Silicate Chemistry.
Petrovite was born in a fiery place in the wild, but Filatov said researchers could look into synthesizing a compound with its same structure in a lab for use in battery development. That would be quite a journey from a volcano to powering gadgets in people's homes.
Sources: https://www.cnet.com/news/scientists-discover-beautiful-blue-new-mineral-petrovite/, https://en.wikipedia.org/wiki/Petrovite, https://bigthink.com/surprising-science/newly-discovered-mineral-petrovite-could-revolutionize-batteries?rebelltitem=3#rebelltitem3, Cambridge University Press.
The Chemical Structure of Petrovite with copper centers surrounded by seven oxygen atoms shared in silicate tetrahedrons
Petrovite found in the Kamchatka Peninsula of Russia with a color that gives clues to its copper-centered chemistry.
The Beautiful Green Hulk of a Gem!
Sphene comes from the Greek word “sphenos,” meaning wedge, a reference to the mineral’s characteristic wedge-shaped crystals. Sphene or titanite belongs to the titanite mineral group as the titanium-rich (Ti) member. It’s the only member of this group commonly used as a gemstone. While mineralogists officially use the term titanite to refer to this stone, many gemologists use the term sphene. By either name, however, these striking gems remain little known to most jewelry connoisseurs, despite reasonable availability.
Sphenes frequently come in yellow, orange, brown, and green hues, with many gradations between them, and often show color zoning. Iron (Fe) and rare-earth element impurities create these typical colors. Chromium (Cr) colors the rare “chrome sphene” variety an intense green. Sphenes can also occur colorless, red, blue, black, and brown.
Sphene’s dispersion or fire ranks among the highest in the gem world. However, its body color, degree of inclusions, cutting orientation, and cutting style may enhance or obscure this feature. Sphene is often pleochroic, showing more than one color depending on the angle from which you view it; sphene’s transparent specimens are notable for their trichroism, showing three different colors.
Sphene has rich body colors, strong trichroism, and a fire that exceeds diamond. The dispersion of sphene is 0.051. A diamond’s dispersion, by comparison, is 0.044. It’s this high number that helps to give the stone such an intense “fire,” showcasing multiple colors, especially when it’s well-cut. Although softer than many more popular gems, sphenes can make wonderful jewelry stones if set and maintained properly.
As with many gemstones, color, clarity, and carat are the most important value factors, followed by the skill and artistry shown in cutting. A preference exists for lighter tones, especially yellows, light oranges, and greens, which best exhibit sphene’s magnificent dispersion. Sphene is usually included and rarely even eye-clean.
Chrome sphene is the most valuable type. The chrome sphene from Baja California is the color of a fine emerald and very rare, especially if clean and larger than one carat. Size is definitely a premium characteristic with this species. Brazilian yellow gem material has a sleepy look and isn’t as bright as that from Baja. Some of the largest and most spectacular green gems have been cut from Indian material.
In general, specimens with reasonably good clarity, strong and attractive body color, and at least some display of dispersion command the best prices.
Sphene’s relatively low hardness (5 to 5.5) and distinct cleavage make it a risky choice for jewelry. However, it also possesses gemological properties that make it a desirable piece for collectors as well as adventurous jewelry enthusiasts. It set properly, and worn with care, it makes a distinctive collector's choice.
Sources: hhttps://www.gemsociety.org/article/sphene-jewelry-and-gemstone-information/, https://en.wikipedia.org/wiki/Titanite, https://www.nationaljeweler.com/articles/976-5-things-to-know-about-sphene
Scientist Discover a New Route for Complex Crystal Creation
Article by Beth Mundy, Pacific Northwest National Laboratory. Researchers used advanced microscopy techniques to watch mesocrystals form in real-time.
Image Credit: Composite image by Mike Perkins | Pacific Northwest National Laboratory
When materials reach extremely small size scales, strange things begin to happen. One of those phenomena is the formation of mesocrystals.
Despite being composed of separate individual crystals, mesocrystals come together to form a larger, fused structure that behaves as a pure, single crystal. However, these processes happen at scales far too small for the human eye to see and their creation is extremely challenging to observe.
Because of these challenges, scientists had not been able to confirm exactly how mesocrystals form.
Now new research by a Pacific Northwest National Laboratory (PNNL)-led team used advanced transmission electron microscopy (TEM) techniques to see mesocrystals form in solution in real-time. What they saw runs contrary to conventional wisdom and their insights could one day help scientists design materials for energy storage and understand how minerals in soil form.
Rather than individual crystals nucleating, the step that begins crystal formation, and then randomly aggregating into mesocrystals in two unrelated steps, the researchers observed that nucleation and attachment were closely coupled in forming these highly uniform structures. The researchers reported their work in the February 18, 2021 issue of Nature.
"Our findings identify an important new pathway of crystallization by particle attachment and resolve key questions about mesocrystal formation," said PNNL and University of Washington materials scientist Guomin Zhu. He was part of the research team led by Jim De Yoreo, PNNL materials scientist and co-director of the Northwest Institute for Materials Physics, Chemistry, and Technology. "We suspect this is a widespread phenomenon with significant implications both for the synthesis of designed nanomaterials and for understanding natural mineralization," Zhu added.
Seeing Crystallization in Real-Time
The project took years to execute and required significant problem-solving. For the microscopy experiments, the scientific team chose a model system that included hematite, an iron compound commonly found in the Earth's crust, and oxalate, a naturally abundant compound in soil.
They visualized the process using in situ Transmission Electron Microscope (TEM) imaging, which gives researchers the ability to see crystallization at the nanometer scale as it happens. They combined this real-time method with "freeze-and-look" TEM that enabled them to follow an individual crystal at different points during growth. Theoretical calculations helped complete the picture, allowing the PNNL team to piece together how the mesocrystals grew.
Researchers generally run most in situ TEM experiments at room temperature to simplify the experimental setup and minimize the potential for damaging the sensitive instrument, but mesocrystal formation rapid enough to observe occurs at around 80 °C.
"The additional equipment used to heat the samples made the experiments extremely challenging, but we knew the data would be key to understanding how the mesocrystals were forming," said Zhu. Once heated, the new hematite nanocrystals make it easy for them to rapidly attach together, which leads, on average, to final mesocrystals of approximately the same size and shape.
Watch as small crystals nucleate near the surface of the growing mesocrystal before attachment. Credit: Video by Guomin Zhu | Pacific Northwest National Laboratory
Transmissive Electron Microscope
TEM Schematic Diagram
Mesocrystals in Nature
The chemical key to this rapid, reliable attachment is the oxalate molecules present in the solution. After the first few small crystals form, the oxalate additives help create a chemical gradient at the interface of the liquid and the growing crystal. More chemical components necessary for particle nucleation linger near the crystals, which dramatically increases the likelihood that new particles will form near existing ones.
While this crystal growth pathway was observed in controlled conditions at very small scales, it likely also occurs in natural systems, according to the researchers. Some mineral deposits, including an Australian hematite deposit, contain mesocrystals. Given the natural abundance of oxalate and the PNNL team's observation that hematite can become mesocrystals at temperatures as low as 40 °C, it seems plausible that this formation route occurs in nature.
Because mesocrystals are found throughout nature, the findings can be applied to understanding nutrient cycling in the environment, among other applications. Moreover, the route to creating near-uniform complex structures requires an understanding of how methods for forming such materials work and how to control them. Thus this work, supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences, opens new possibilities to intentionally create mesocrystals or mesocrystal-like materials.
Finding amazing Fossils
All of us have the potential to find a once in a lifetime find, including a 4-year-old girl from England.
© Amgueddfa Cymru - National Museum of Wales
The 10-cm long footprint was discovered by Lily Wilder near Bendricks Bay in south Wales, on January 30, 2021.
Paleontologists stunned by a perfectly preserved dinosaur footprint discovered by a 4-year-old girl
by Sophia Ankel (firstname.lastname@example.org)
Lily Wilder made the discovery on January 23 while walking along a beach in South Wales with her father and dog. The family was on their way to the supermarket when Wilder saw the footprint imprinted on a rock.
"It was on a low rock, shoulder height for Lily, and she just spotted it and said, 'look, Daddy,'" her mother, Sally Wilder, told NBC News. "She is really excited but doesn't quite grasp how amazing it is."
At first, the family thought the print, which is just over 10 cm (4 inches) long, was scratched out on the rock by an artist. But mother Sally was aware that similar footprints had been found along that piece of the coast before, so she posted about their discovery on social media.
"I found this fossil identification page on Facebook and I posted it on there and people went a bit crazy," she told Wales Online. Shortly after, The National Museum of Wales was in touch with the Wilder family, and officials have since retrieved the print and put it in the museum. The family says their daughter's interest in dinosaurs has been ignited since the discovery and that she's been playing with a collection of dino toys and models.
Experts believe the footprint was most likely left by a dinosaur that stood about 75 centimeters (29.5 inches) tall and 2.5 meters (about 8 feet) long and walked on its two hind feet. It is impossible to identify exactly what type of dinosaur left it, although experts typically classify the print as a Grallator.
Welsh scientists are calling the girl's discovery "the finest impression of a 215 million-year-old dinosaur print found in Britain in a decade," according to Wales Online. "It's so perfect and absolutely pristine. It's a wonderful piece," said Karl-James Langford from Archeology Cyrmu, according to Wales Online. "I would say it's internationally important and that is why the museum took it straight away. This is how important it is. I would say it's the best dinosaur footprint found in the UK in the past 10 years," he added.
The National Museum in Cardiff, which is currently closed due to the COVID-19 pandemic, said that Lily and her classmates would be invited to the exhibition once it reopens. "What's amazing is, if her name goes down as the finder in the museum, it could be her grandchildren going to visit that in the museum one day, and for years and years and generations to come, which is quite amazing," mother Sally told Wales Online.
Go out and find your amazing find of a lifetime!
Proustite is an interesting mineral that contains silver in its chemical structure. It is one of the few silver-bearing minerals that can exhibit transparency. Proustite is usually transparent, with deep-red crystals, but may also be a darker, more metallic-looking form. However, even darker, more metallic Proustite will be visibly red and transparent when backlit.
Proustite is light sensitive. Prolonged exposure to bright light will darken its transparency and cause it to become darker. Exposure also may cause a dark, dull film to form on crystal faces; this film can be removed by brushing a specimen with soap and water.
Proustite is very similar to Pyrargyrite, and forms a series with it. Proustite is the arsenic-rich member, and Pyrargyrite is the antimony-rich member. It is often not possible to visually distinguish these two minerals from each other, though Proustite is usually lighter in color. Most good material in collections today are from closed, historical localities. Several classic European localities have produced highly desirable Proustite specimens. Relatively large crystals have come from the Erzgebirge in Germany at Freiberg, Schlema, and the Schneeberg Districts. Across the border in the Czech Republic, some of the earliest sources Proustite have come from Jáchymov, Krušné Hory Mts, Bohemia. Small Proustite crystals, often associated with Quartz, were once found in the Ste Marie-aux-Mines, Haut-Rhin, Alsace, France.
A more recent producer of good Proustite crystals is Morocco, at the Imiter and Bou Azzer mines. In South America, some of the best examples of this mineral have come from Chañarcillo, Copiapo Province, Chile; and the Uchucchacua Mine, Oyon, Lima Department, Peru. In Canada, good crystal clusters and crusts of Proustites have come from the Cobalt region, Timiskaming District, Ontario
It forms prismatic crystals, often complex in form. Crystals are often elongated scalenohedrons with complex terminations. Also in blocky groups of stubby crystals, interpenetrating crystals, grainy, encrusting, botryoidal, globular, and massive. May also form in intergrowths of three crystals, forming a trilling. Crystals are usually striated horizontally on an angle and may have complex growths and angles.
Named by François S. Beudant in 1832 in honor of Joseph-Louis Proust (26 September 1754, Angers, France – 5 July 1826, Angers, France), chemist and actor, for Proust's work on the red silver minerals (proustite-pyrargyrite series). He is most famous for discovering the law of definite proportion, stating that chemical compounds always combine in constant proportions.
It has several other names that it is often called like Ruby Silver, Red Silver, Tears of Jesus, Blood of Christ, and Red Silver Ore. Proustite is a sulfosalt mineral consisting of silver sulfarsenide, Ag3AsS3.
How Squishy Animals Evolved Strong Shells and Bones
From Futury, Science Magazine and the NCBI
The animal kingdom abounds with creatures that grow hard shells, carapaces, and skeletons. But complex life was pretty squishy at the beginning. A new study clarifies how and when things changed.
Animals with skeletons did not exist before about 550 million years ago. Then, scientists have proposed, atmospheric oxygen levels rose and the chemistry of the oceans changed in such a way that animals could harness the minerals required to build hard structural parts. A new analysis of ancient rock layers in Siberia provides support for this idea, showing that the oceans became rich in skeletal building blocks around the same time the first fossils of animals with skeletons start to appear.
Researchers discovered that when carbonate skeletons were first evolving more than 500 million years ago, diverse groups of animals all converged on a similar, counterintuitive process for biomineralization. Today, many unrelated animals build their skeletons or shells out of calcium carbonate—including echinoderms, mollusks, and corals. Instead of building crystals ion-by-ion from the surrounding seawater, these animals use amorphous, or non-crystalline, nanoparticles as their building blocks of choice.
“In fact, crystallization by particle attachment actually seems to be the prevailing method of biomineralization as far as we can tell,” says Susannah Porter, a professor of earth science at the University of California, Santa Barbara.
Rather than building their skeletons at a molecular level, these animals first form nanoparticles of amorphous calcium carbonate. They then store these particles in vesicles that they can use to transport them to the site of crystallization. This method of crystallization was first documented more than 20 years ago in the teeth of sea urchins. Since then, scientists have noticed the process throughout the animal kingdom and involving different
minerals. What’s more, the different groups of animals seem to have independently settled on this method of biomineralization, so it must have something going for it. Given its ubiquity, Porter and her collaborators wanted to determine how far back they could find evidence of this process. Their findings appear in PNAS.
“We obviously can’t watch these Cambrian and Ediacaran organisms make their skeletons, so we need to have a proxy,” Porter says. First author Pupa Gilbert, of the University of Wisconsin-Madison, had previously found that crystallization by particle attachment leaves an irregular particulate texture in the shells and skeletons when they’re viewed under a scanning electron microscope. The team saw this same tell-tale pattern upon imaging fossils more than 500 million years old. In fact, this signature preserved even in the material that had subsequently converted into another mineral.
“It’s spectacular,” Porter says, “the fact that we can see this detail at the sub-micrometer level.” Among the ancient material, Porter and her collaborators examined were fossils of Cloudina, a genus that includes some of the earliest animals that formed a mineralized skeleton. The genus was named after Preston Cloud, a late professor of biogeology and preeminent researcher in the study of early life. The team saw the same irregular nanoparticulate texture in Cloudina fossils as in other animals that form crystals by particle attachment. “This shows that even when animals were first evolving mineralized skeletons, and were maybe not so good at biomineralizing, they were already choosing this mechanism,” Porter says.
The findings suggest that, even early on, there was a selection for this particular mechanism across different
lineages. “When you see something that is selected for over and over again, it suggests that it is the most
advantageous one,” Porter says.
Although it’s counterintuitive that animals would use amorphous material to create the crystals that ultimately form their skeletons or shells, Porter says that this mechanism seems to permit greater control over mineralization than simply building ion by ion, as the traditional models suggested. For one, these particles are incredibly stable when confined in vesicles: The material doesn’t immediately crystallize but remains amorphous. This allows the animal to keep ingredients around and available yet maintain flexibility regarding when and where the mineralized skeleton forms.
Additionally, compounds like calcium carbonate can take different structures—thereby forming different minerals—depending on environmental conditions. By storing the molecules in an amorphous state, the animal can better control what form, or polymorph, they become, Porter explains.
“It’s like having some frozen cookie dough around that you’re later going to bake into cookies,” she says. Porter is interested in the large-scale patterns of when lineages first evolved skeletons and how environmental and ecological conditions of the time affected those skeletons. She suspects that the earliest biomineralizers, like Cloudina, didn’t have particularly strong control over the process of building their skeletons. “But by the time you get to the Cambrian, the carbonate mineralizers have shells that are complex and organized,” she says. “They have much greater control over their skeletons.”
Specimens of Cloudina, which, known from sites around the world, is one of the earliest skeletal animals
To understand the link between rising oxygen levels and the evolution of skeletons, Rachel Wood, a geobiologist at the University of Edinburgh, and her team studied ancient rock layers found deep in Siberia’s wilderness near the Yudoma River. The rocks, formed from layers of sediment deposited in ancient oceans, contain not only fossils but also sedimentary clues to how the oceans’ chemistry shifted during the time when skeletons are thought to have arisen. Wood spotted a series of ocean chemistry shifts during the Ediacaran and Cambrian periods, which together stretch from about 635 to 485 million years ago. Until roughly 545 million years ago, the rocks are rich in the mineral dolomite, which is believed to have formed in the oceans when oxygen levels were low, Hood says. After that, as levels of atmospheric oxygen increased, limestone rock predominates.
The limestone at the field site contains the minerals aragonite and calcite, which animals need to build skeletons; aragonite and calcite crystals form much faster and with less energy than dolomite, allowing animals to harness them for skeleton building in a way they can’t with dolomite.
This skeletal revolution is reflected in the rocks themselves. In the dolomite-rich layers, the fossils of soft-bodied organisms predominate—like Aspidella, a soft, frond-shaped creature that anchored itself to the seafloor. Then, in the limestone, one of the first known skeletonized animals appears—Cloudina, a millimeter-scale creature made of a calcified shell that looks like a stack of ice cream cones. From such beginnings, skeletonized animals would go on to evolve into such familiar forms as fish, shellfish, dinosaurs, and, eventually, humans.
As much as exoskeleton added speed to the evolution of animal life in general and created opportunities for animals to expand their activity radius by using calcified extremities and protection shields, it also imposed limitations, associated mostly with limited body size and lack of surface sensory organs. In addition, rigid shells and shields did not allow much movement and locomotion; therefore, the next major change in the evolution of skeleton—dislocation of mineralized skeleton from the outside to the inside of animal bodies, proved to be a major adaptive advantage. Especially in animal lineages that later gave rise to vertebrates, the appearance of endoskeleton enabled the expansion of activity radius and habitation of entirely new environments (Bennet 1991). In addition, those developments encouraged the development of a strong muscular system and added further adaptive values such as greater overall mobility and the appearance of a regenerative and environment-sensitive outer dermis (Ruben and Battalia 1979, Ruben and Bennett 1980).
Another major advantage of the architecture of mineralized skeleton was the development of an attribute of bone that decisively set vertebrates apart from virtually all other multicellular eukaryotes. The hard mineral fraction consisting mainly of calcium carbonate, which had been used over millions of years to build all forms of marine exoskeletons, was replaced by calcium phosphate, mostly in the form of calcium hydroxyapatite (Ruben and Bennett 1981, Ruben and Battalia 1992, Omelon et al. 2009). But why did vertebrates choose an entirely new mineralization strategy, and what special properties of calcium hydroxyapatite led to its integration into early vertebral skeletons?
A possible advantage of the novel chemical composition of vertebrate skeletons might be that calcium hydroxyapatite building blocks provide greater chemical stability. This may have been important, especially in the acidic environments created after bursts or periods of intense physical activity—conditions that are typical of most vertebrate species (Ruben and Battalia 1979, Ruben and Bennett 1981). Hydroxyapatite builds a more stable mineral component of the skeleton than can be achieved with a calcitic material, which is particularly important at pH ranges that are associated with the intense activity and a high-energy consuming lifestyle typical of vertebrates.
So which came first: The Tooth or the Shield?
In the earliest skeletal structures in vertebrate fossils, the tooth-like structures came before animals eventually developed boney dental-like structures for the protection of the skin. Early teeth and the forerunners of bony skin plates appear to be the product of the same genetic machinery, regulating epithelial/mesenchyme interactions and able to produce similar structures at different locations.
Sources: https://www.futurity.org/carbonate-skeletons-evolution-2153532/, https://www.sciencemag.org/news/2016/11/how-did-animals-get-their-skeletons, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3237026/, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3237026/
The Nine Scariest Rocks & Minerals
Inspired by Forbes Magazine (Feb 14, 2016)
Lead found in Flint, Michigan water is an unfortunate example of negligence leading to the mass exposure of elemental lead found naturally or man-made. Much in the same way humans communicate warnings of deadly plants and animals, it's important to communicate the risks and exposure of deadly rocks and minerals.
It's easy to forget how lethal our natural world can be, where an encounter with the wrong rock or mineral could lead to injury or death. Often times toxic minerals are associated with materials we use every day for construction, computers, and cosmetics. With a keen eye and an understanding of toxicity, you can help to identify deadly minerals in your surrounding.
The Deadliest Rocks & Minerals -
Chalcanthite - CuSO4·5H2O
The brilliant blue Chalcanthite is hydrated water-soluble copper sulfate. The mineral is used to ore copper, however, it's necessary to keep the environment dry as the mineral can easily dissolve and recrystallize in a wet environment. The water solubility of this mineral can easily lead to copper poisoning of an environment and is toxic to humans.
Stibnite - Sb2S3
Stibnite is a toxic antimony sulfide mineral with an orthorhombic crystal lattice and a source of metalloid antimony. Stibnite paste has been used for thousands of years for cosmetics to darken eyebrows and lashes. The mineral was also used to make eating utensils, causing poisoning from antimony ingestion.
Asbestos - Mg3Si2O5(OH)4
You have likely heard of the mineral asbestos and associate it with lung cancer. This silicate mineral grows thin fibers crystals that can easily break off and form dust particles. Despite its usefulness in insulation, fire resistance, and sound absorption, the mineral dust is deadly if inhaled. The fibers can cause lung cancer, mesothelioma, and asbestosis.
Arsenopyrite - FeAsS
Arsenopyrite is an iron arsenic sulfide with a brilliant steel metallic color often found in hydrothermal vents and pegmatites. The arsenic leads to a number of environmental and human dangers and can sometimes be associated with gold deposits. Oxidation of arsenopyrite can lead to soluble arsenic in water and subsequent arsenic poisoning of the groundwater.
Cinnabar - HgS
Cinnabar is a deep red mercury sulfide mineral that provides much of the world's elemental mercury. Despite the brilliant red color and history of use in trading and as a coloring agent, Cinnabar is deadly. Mercury is toxic to humans and was a source of death from many mines around the world. Ironically, long ago some cultures considered Mercury to be a longevity agent and consumed it leading to death.
Realgar - As4S4
Realgar is an arsenic sulfide mineral, also known as "ruby sulfur" or "ruby of arsenic". It is very pretty and another bright red "gemmy" looking mineral. It was used by firework manufacturers to create the color white in fireworks prior to the availability of powdered metals such as titanium. It is still used in combination with potassium chlorate to make a contact explosive known as "red explosive" for some types of torpedoes and other novelty exploding fireworks branded as 'cracker balls'. Realgar is toxic. It is sometimes used to kill weeds, and rats.
Hutchinsonite - (Tl,Pb)2As5S9
Hutchinsonite is a form of arsenic sulfide with thallium and lead that can be found in hydrothermal vents. Thallium salts are nearly tasteless and highly toxic and have been used in rat poison and insecticides. The thallium inclusion in this arsenic sulfide combines two extremely dangerous and deadly minerals. Exposure to this mineral can potentially lead to death.
Torbernite - Cu(UO2)2(PO4)2 · 8 - 12 H2O
Torbernite is a dangerous mineral composed of hydrated green copper, phosphate, and uranyl. The mineral is often found in granites that contain uranium and is dangerous due to its radioactive nature. The mineral releases radon naturally and can cause lung cancer if exposure is long enough.
Uraninite - UO2
Uraninite is a uranium oxide mineral and the most important ore of uranium. Uraninite is highly radioactive and should be handled and stored with care. “Pitchblende” is an archaic name that was used for uraninite and other black materials with a very high specific gravity into the late 1800s and early 1900s.
The rocks and minerals above are toxic yet some are rather rare. Many of the elements in them like arsenic, uranium, and lead are known to be dangerous to people because they are poisonous or radioactive. Elements like arsenic and copper can build up in the environment and become more and more toxic. In many instances mine collapse, or equipment failure can be much more deadly than the ore that is being mined. Or, minerals like gold or diamonds are dangerous from the standpoint that they can lead to loss of life because other people will kill for them. Even mundane minerals like quartz or silicon oxide can lead to life-threatening diseases like silicosis if you are exposed to fine dust that can build up in the lungs. While our collecting hobby is fun and has many beautiful examples, harmful minerals should be handled with great care!
Sources: From Forbes Magazine and Senior Contributor Trevor Nace found at https://www.forbes.com/sites/trevornace/2016/02/14/9-deadliest-rocks-and-minerals-on-earth/?sh=1a5e6a43659b and Wikipedia images and realgar article. Geology.com was used for Uraninite.
Grow your own Purple Aluminate Crystals at Home
Hi MMS Fans!
In this above videos, we'll demonstrate to you a generally accepted method to grow a wonderful purple single beautiful crystal. For this, we'll require the accompanying substances – potassium and chrome alum. To start, how about we make a blend of alum that can be grown into beautiful octogram crystals.
To do this, take a glass and weight 100 grams of aluminum potassium sulfate and 12 grams of chromium potassium sulfate in it. Including the chromium aluminate will make the solution turn a deep purple color. At that point, pour 400 ml of extremely high temp (over 150 degrees F but not boiling) pure water into the glass and blend until the point when all the alum is dissolved into the water. Very hard water can ruin the process.
Carefully stir the solution until it's all dissolved in the water, leave this glass for a couple of days to give the gems a chance to form at the bottom of the glass container. After a day, carefully empty the alum arrangement into another container and set it aside, do not discard it. You should find a number of small lovely purple crystals that formed at the bottom of the glass. Pick open the mass of the precious stones and place them in a clean glass bowl. Look over the crystals that you pulled out and select the best looking or most interesting crystals. The selected crystals will be the seeds from which a larger crystal will be grown later on.
Tie one of the best seed crystals on a thin fishing line and hang it on a pencil or a stick so it's tied in the middle and hangs down. The best method is a slip knot, which you can look up how to do. Just make sure that it is firmly tied in place and remove any excess fishing line that hangs off the knot. You will be placing this in the solution that you set aside earlier. The solution is a saturated solution if you follow the measurements above. So, as the water evaporates out of the container or glass that you put it in, the excess aluminates will attach themselves to the seed crystal that is floating on the fishing line that you tied the seed crystal in the slip knot. If you want, you can do this with a few of the better crystals you pulled out at the beginning in case your experiment goes wrong or you need to start over. Only do one crystal at a time to get the best results.
Also, remember that you don't want any impurities to get into the solution, so it needs to be someplace that's clean and avoids temperature extremes for the best results. Even dust or flying bugs can spoil the process. You will need to keep an eye on the glass container to make sure that no crystals are forming on the bottom or on the string and remove them. Reheat your solution as shown in the videos and filter it into a new glass vial. Always remember to wear protective equipment and do this only as needed. The more you disturb the process, the more likely that something will go wrong, but if you heed the videos you should get good results.
Over a couple of months, the crystal grows larger and you can decide when its large enough that you want to stop its development. When your satisfied, remove it from the solution and dry its surface with a napkin or paper towel. Once it's completely dry, you can seal it with a couple of layers clear fingernail polish or clear enamel paint. Seal the surface in steps so that it can dry properly between coats. Once the paint is dry, it's safe to handle it and show it off!
And always remember that when you handling chemicals, wear protective equipment and be safe!
Fluorescence in Minerals
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore lower energy, than the absorbed radiation. The most striking example of fluorescence occurs when the absorbed radiation is in the ultraviolet region of the spectrum, and thus invisible to the human eye, while the emitted light is in the visible region, which gives the fluorescent substance a distinct color that can be seen only when exposed to UV light. Fluorescent materials cease to glow nearly immediately when the radiation source stops, unlike phosphorescent materials, which continue to emit light for some time after.
Fluorescence has many practical applications, including mineralogy, gemology, medicine, chemical sensors (fluorescence spectroscopy), fluorescent labeling, dyes, biological detectors, and radiation detection. Fluorescence also occurs frequently in nature in some minerals and in various biological forms in many branches of the animal kingdom (from wikipedia).
Examples of Fluorescent Minerals and some of their properties:
Calcite has been known to fluoresce red, blue, white, pink, green, and orange. Some minerals are known to exhibit multiple colors of fluorescence in a single specimen. ... (Left) Calcite under normal lighting, (Right) Calcite under Short Wave UV Raditons that causes it to emit light in the visible red spectrum. This particular Calcite is from South Africa.
Recently discovered by Erik Rintamaki, Yooperlite® rocks are actually Syenite rocks that are rich in fluorescent Sodalite. Yooperlites® can be searched for on Michigan beached using a good UV spectrum LED flashlight and are usually found In the Upper Peninsula of Michigan, anywhere from Whitefish Point to Grand Marais.
Fluorite...The original Fluorescent Mineral
One of the first people to observe fluorescence in minerals was George Gabriel Stokes in 1852. He noted the ability of fluorite to produce a blue glow when illuminated with invisible light "beyond the violet end of the spectrum." He called this phenomenon "fluorescence" after the mineral fluorite. The name has gained wide acceptance in mineralogy, gemology, biology, optics, commercial lighting, and many other fields. Many specimens of fluorite have a strong enough fluorescence that the observer can take them outside, hold them in sunlight, then move them into the shade and see a color change. Only a few minerals have this level of fluorescence. Fluorite typically glows a blue-violet color under shortwave and longwave light.
How Many Minerals Fluoresce in UV Light?
Most minerals do not have a noticeable fluorescence. Only about 15% of minerals have a fluorescence that is visible to people, and some specimens of those minerals will not fluoresce. Fluorescence usually occurs when specific impurities known as "activators" are present within the mineral. These activators are typically cations of metals such as: tungsten, molybdenum, lead, boron, titanium, manganese, uranium, and chromium. Rare earth elements such as europium, terbium, dysprosium, and yttrium are also known to contribute to the fluorescence phenomenon. Fluorescence can also be caused by crystal structural defects or organic impurities.
In addition to "activator" impurities, some impurities have a dampening effect on fluorescence. If iron or copper are present as impurities, they can reduce or eliminate fluorescence. Furthermore, if the activator mineral is present in large amounts, that can reduce the fluorescence effect.
UV Lamps for Viewing
Scientific-grade lamps are produced in a variety of different wavelengths. They will often produce UV light in different ranges for UV-A (LW), UV-B (MW), or UV-C (SW) radiation. Most minerals react strongest under UV-C lights and always wear eye & skin protection to not burn yourself! (geology.com)
Michigan's other Petoskey Stones
Charlevoix Stones, Favosites & Fossilized CorAls
We are poking fun, but Michigan is such a great place to collect rocks, why not add some more help in finding interesting stuff on our shorelines and driveways that look like Petoskey Stones, but they're not! A Pesotsky Stone is a fossilized coral, a Charlevoix Stone is a fossilized coral, and a Favosite is a fossilized coral, but a Favosite is not a Petosky stone. Clear??
The Charlevoix stone looks a lot like its cousin, the Petoskey stone. It’s smaller in total size but is especially distinguished by its smaller honeycomb-like corallite patterns. The two are sometimes confused, and it's easy to see why: Both are shades of soft gray or beige, freckled with honeycomb patterns, and are found in the same areas around Michigan, usually along shorelines in the northern parts of the state. Like the Petoskey stone, the Charlevoix stone is a remnant from the ancient period of Earth history when the land that we now call Michigan sat at the bottom of a shallow sea.
Paleontologist Jen Bauer, a research museum collection manager at the University of Michigan’s Museum of Paleontology, said that while both Charlevoix and Petoskey stones are fossilized coral, the two are from different taxonomic groups: Petoskey stones being from the major group “Rugosa,” while Charlevoix stones are from the group “Tabulata,” a nod to the tabulae, or small square-ish shapes, that make up their intricate design.
While the two groups’ time on Earth overlapped, the coral species that gave us Charlevoix stones were much longer lived. Charlevoix stone coral belongs to the now-extinct genus Favosites, which existed on the planet for nearly 200 million years, some 450-250 million years ago. Favosites consist of a series of calcitic tubes (corallites) packed together as closely as possible, thus the resemblance to a honeycomb. The openings for the coral polyps are much smaller than in Petoskey stones and look like a lace pattern draped over the rock.
Meanwhile, the genus of coral that included the Petoskey stone, Hexagonaria, was around for less time -- about 57 million years. (For a mind-bending comparison, consider that anatomically modern humans are generally believed to have been around for only about 200,000 years.)
The reason both Charlevoix and Petoskey stones are so prevalent here in Michigan is due not only to our state’s geological past but also it's present. “Michigan’s history is pretty unique,” Bauer said. “We also have these really beautiful lakes that churn up the stones. You could find these corals in other places, but you don’t find the really beautiful polished stones like you do in Michigan.”
Sources: https://www.mlive.com/news/2020/07/meet-the-charlevoix-stone-a-petoskey-lookalike-thats-become-a-michigan-rock-hunting-treasure.html, https://greatlakeslocals.com/12-collectible-rocks-and-fossils/
Petoskey Stone and Charlevoix Stone
A Nice Tumble of Charlevoix Stones
The Art of Crystals from a Human Perspective
Many of us collect crystals and minerals because we find them beautiful. We would venture to guess that's what got the majority of us hooked on collecting them in the first place. We find them beautiful in many ways. But have you ever thought of using crystals as the subject of art, just like how many painters will paint a still life scene? It's not an easy thing to do. Crystals and minerals display all kinds of interesting visual characteristics like transparency, refraction, reflection, polarization, dichromism, and more. In fact, they are quite difficult to successfully depict in artistic media like watercolors, colored pencils, or even in computer-aided design programs. They are mathematical, symmetrical, and natural all at the same time.
We thought that some examples and a couple of visual tutorials might help us all pass the time and ponder the artistic beauty and difficulty of painting crystals. Check these out and see if you can do it too.
Follow the Seven Steps by CGCookie
This example works best for CGI and Oil Painting.
1) Draw the outline of your crystal or gemstone. If you're on a computer program, do this on its own layer separate from the other steps. 2) Fill it in with a solid color. 3). Add in some color tones and shades on each face. Remember to think about which way the light is pointing at your object and be consistent with how the light would hit the object. 4) Remove/Erase the outlines. 5) Add is some inclusions and refractions on the object. 6) Paint on so highlights using white or the color of your light sources that really adds contrast and depth. 7) Add in shadows and depth to make it look 3D.
Click to Download for Practice
Drawing a Cluster of Crystals
Practicing the Techniques
Click to Download for Practice
A Practice Page for Fun
Click to download this and have fun. It's no easy thing to do. It takes practice and patience to be able to color in convincing crystals and perhaps it will give you a bit more respect for those artists and scientists who spend many hours creating the illustrations that we marvel at and enjoy.
The Artist James Brunt
We have been waiting a few months for the right time to post this unique and awe-inspiring artist's work. Why did we wait you might ask? Well, because we thought his work was so unique and paid homage to the great stonemasons and neolithic builders of the past, as well as being something fun that any of us could do to emulate the wonder of what he generates. During this time that many of us are home, and perhaps are looking for ideas to do with our family or just for ourselves, we thought it would be a great time to post this.
If these inspire you, go out and create your own cairns and landscape-based art, and in turn, maybe you will inspire others too!
About the Artist
James Brunt creates elaborate ephemeral artworks using the natural materials he finds in forests, parks, and beaches near his home in Yorkshire, England. This form of land art, popularized and often associated with fellow Brit Andy Goldsworthy, involves detailed patterns, textures, and shapes formed using multiples of one kind of material. Brunt collects twigs, rocks, and leaves and arranges them in mandala-like spirals and concentric circles. He photographs his finished work to document it before nature once again takes hold of his materials. The artist frequently shares updates via Twitter and Facebook where he sometimes invites the public to join him as he works. Brunt also offers prints of his photographed artworks on his website.
Figure A: Orangish Powellite, Apophyllite, and Scolecite
Figure B: Scolecite Spray (click to enlarge)
Figure C: Scolecite Crystal needles
Figure D: Scolecite and Stilbite Spray (click to enlarge)
Figure E: Scolecite Spray (click to enlarge)
Figure F: Pale Green Apophyllite with Scolecite from India
Figure G: Scolecite carved sphere. Sometimes Scolecite is carved into sculptures and more rarely carved into gemstones.
Here we have one of the extensive zeolite family of minerals that usually precipitates from warm mineralized fluids in volcanic settings, circulating in the Earth in heated convection cells. it was first described in 1813 and named after it’s pyroelectric reaction in the flame of a blowpipe (which used to be a standard mineralogical test way back when, in this case, a voltage is generated across the crystal when heated). It is a secondary mineral, growing in cavities within the lava such as gas bubbles. It also occurs in metamorphic rocks, when fluids released from higher temperature rocks below during their transformation by heat and pressure percolate upwards and precipitate their chemical contents upon encountering different temperatures or chemical conditions.