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What Kind Of Minerals and Crystals Can Be Found In Ohio?

Ohio Fluorite
Calcite celestite Pugh Quarry, Custar, Ohio

Calcite and celestite crystals from Ohio

If you live in Ohio and want to get rich finding Emeralds then forget it. Your best bet for that is to move to the Asheville, NC. Our state just doesn’t have the Geology necessary for that sort of gemstone to be present. It’s true people do find gold and diamonds (six of those have been found in Ohio, not including those found in jewelry stores) in Ohio, but those are travelers that arrived courtesy of glaciers and deposited in glacial sedimentary deposits.

But just because you can’t fill a jewelry shop from our geology doesn’t mean that Ohio isn’t rich in crystal treasure. Our state is blessed with minerals that are used industrially and helped turn the state into an Industrial powerhouse. It also is a source of beautiful minerals perfect for a collection or as a display piece (Celestite, I am looking at you!) And don’t get me started talking about fossils! Cincinnati is famous for its rich troves of Ordovician era fossils on the Cincinnati Arch. You know where to go if you want a Trilobite.

Since most locals aren’t aware of our state’s Geology, let alone that we have a geology, or if we have one, where somebody may have misplaced it, how much it’s worth and whether you can trade it to rent Top Gun: Maverick on Amazon, we are presenting a curated list of the crystals and minerals found in the Buckeye state.

Photo credit for image above: Photo By James St. John – https://www.flickr.com/photos/47445767@N05/33229612163/, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=96284794

Calcite

Calcite crystals Gibraltar Island Lake Erie Ohio

Sunlit Silurian calcite from Put-in-Bay in Ohio on Lake Erie.

Photo By James St. John – https://www.flickr.com/photos/47445767@N05/50588186197/, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=96284996

Calcite is found throughout Ohio in different forms as granular aggregates in black shale in eastern and central Ohio, and as crystal and granular aggregates in Western Ohio.

The name calcite comes from a Greek word meaning lime. This comes from its chemical component, Calcium Carbonate, which sometimes is mistakenly known as “lime.” Calcite is known in more than 300 forms of crystals. The scalenohedral crystals of Calcite, one of its most common varieties, ordinarily are known as “dogtooth spar” or “dogtooth calcite” because of their resemblance to a dog’s canine tooth. Another variety, transparent rhombohedral calcite, is used in optical equipment. Although they are not specific varieties of calcite, stalactites, stalagmites and other formations found in caverns are made of calcite.

Calcite is one of the most common minerals, making up about 4% by weight of the Earth’s crust. Calcite is common as vein fillings in many rocks in western and central Ohio. Silurian dolomites in northwestern Ohio yield clusters of large crystals ranging from clear to dark brown. Many have a golden color.

Crystals and granular aggregates in cavities and fractures of dolostones and limestones in western Ohio; granular aggregates commonly form veins in dolostone concretions and less commonly in ironstone concretions from black shales in central and eastern Ohio; more rare as an efflorescence.

Calcite (CaCO3) is a soft carbonate mineral that occurs in various colors, including white, yellow, brown, gray, black, and pink, and also can be colorless. Calcite is a common mineral that occurs primarily in limestone and dolostone, occasionally in concretions and rarely as an efflorescence.

The Romans made concrete by mixing lime and volcanic ash to create a pozzolanic reaction. If this was mixed with volcanic tuff and placed under seawater, the seawater hydrated the lime in an exothermic reaction that solidified the mixture.

Aragonite

vug with aragonite east central ohio

Vug with aragonite crystals in arenaceous, ferruginous, fossiliferous limestone from Ohio

Photo By James St. John – Vug with aragonite crystals in arenaceous, ferruginous, fossiliferous limestone (Vinton Member, Logan Formation, Lower Mississippian; Mt. Calvary Cemetery Outcrop – Rt. 13 roadcut, Heath, east-central Ohio, USA) 3, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=82971990

With a name that sounds like a heroic character in J.R.R. Tolkien’s The Lord of the Rings, but originates from the territory of Aragon in Spain, aragonite is one of the three most common forms of calcium carbonate. Its crystal lattice differs from calcite, one of the other common forms of calcium carbonate. It has a host of industrial uses. Aragonite has been found in Coshocton County.

Celestite

Celestite Crystals inside Crystal Cave on South Bass Island

Crystal Cave is a small cave in Put-in-Bay on Lake Erie in Ohio touted as the world’s largest geode. An abundance of large, well-formed crystals of celestite cover the walls. The cave was originally mined for its strontium content, but enough nice crystals still remain to keep the site open as a show cave.

Photo by James St. John – Celestite (Crystal Cave, South Bass Island, Lake Erie, Ohio, USA) 16, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=82969277

A soft sulfate mineral ore of strontium, in fact being the most common mineral that contains strontium. Celestite derived strontium is used industrially in fireworks, ceramic magnets, and toothpaste

Ohio is famous for having some of the best celestite deposits in the world. The mineral is found in 11 counties. The northwestern regions of Ohio amid the Findlay Arch produce celestite ranging in color from white to pale blue. The area of Serpent Mound southwestern Ohio also produces some celestite due to an unusual geological occurrence. South Bass Island is a huge vug filled with very large celestite crystals.

Quartz

Geode with sphalerite barite dolomite and quartz Monroe County Ohio

Close-up of a Monroe County, Ohio geode with sphalerite, barite, dolomite and quartz.

Photo by James St. John – Geode with sphalerite, barite, dolomite, and quartz (Monroe County, Ohio, USA) 2, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=84692026

What can’t you not say about quartz? It is a hard silicate in the form of silicon dioxide. It’s useful in glassmaking, watchmaking, ceramics, metal casting, electronics, and the petroleum industry. But the enduring love it receives is because of it’s beauty and variety: rose quartz, lavender quartz, blue quartz, rutilated quartz, citrine, amethyst, enhydro quartz, prasiolite, ametrine and a variety of shapes including points, needles, and clusters.

In Ohio, quartz is found in flint beds in Coshocton, Licking, and Muskingum Counties; in Adams and Highland Counties; in septarian limestone concretions in the central portion of the state; and loose in streambeds and creeks in the Southeast.

Fluorite

Ohio Fluorite

An example of Ohio Fluorite from Stoneco Auglaize quarry (Maumee Stone County quarry), Junction, Paulding County, Ohio.

A 1.2 cm colorless cube with well-centered, distinct, rich purple color “phantom” inside. The crystal has very sharp faces and excellent gemminess. It sits upon a small amount of Dolostone matrix

Photo by Rob Lavinsky, iRocks.com – CC-BY-SA-3.0, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=10148353

Fluorite is a another name for calcium fluoride, a halide ore mineral of fluorine. It’s has several industrials uses including as a flux for removing impurities in the manufacture of steel and in the production of fluorine gas which itself is used in the refining of uranium.

While fluorite is found across the world, the quality and largest quantities are mined out of Europe and North America. In Ohio fluorite is found in 19 counties. Typically cubic crystals found in dolostones in northwestern Ohio particularly along the edges of the Findlay Arch and occasionally in the Serpent Mound area.

Some fluorite is UV reactive, fluorescing under exposure. Because of this property, it and it’s compounds are used to manufacture synthetic crystals with applications in laser and special UV and infrared optics.

Dolomite

Put-in-Bay Dolomite South Bass Island, Lake Erie,Ohio

Ohio Dolostone. In the past Dolomite was used to refer to both the mineral and the rock. Dolomite is now used to refer to the mineral and dolostone refers to sedimentary rock whose primary content is dolomite.

Photo By James St. John – Put-in-Bay Dolomite over Tymochtee Dolomite (Upper Silurian; South Bass Island, Lake Erie, Ohio, USA) 6, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=82969360

What relationship does Ohio have with a nineteenth century french geologist? The answer in one word is Dolomite! Named after Déodat Gratet de Dolomieu, Dolomite is found in over 19 Ohio counties. Dolomite differs from limestone in that it contains both calcium and magnesium.

More well known as an Indiana mineral, especially the Corydon area, this calcium magnesium carbonate occurs in small crystals in western Ohio and along the Huron river among other areas.

Dolomite has industrial uses including as a source of magnesium salts like magnesia and by builders as structural and ornamental stone.

The term dolomite used to refer both to the mineral dolomite and dolostone (a sedimentary rock of which is made primarily of dolomite).

Barite

Fluorite and barite (quarry in Marblehead Peninsula, far-northern Ohio

Fluorite and barite from Marblehead Peninsula Ohio

Photo By James St. John – Fluorite and barite (quarry in Marblehead Peninsula, far-northern Ohio, USA), CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=40022633

Found in over 26 counties in Ohio, this Barium Sulfate mineral often associated with calcite and other minerals is often white or colorless but can also have light blues, greys, yellows or browns. In the central and eastern Ohio black shale formations barite is found in concretions such as limestone, ironstone and pyrite. In the northwestern and southwestern Ohio crystalline or granular barite can be found in fractures and cavitiesof dolostones (dolomite sedimentary rock).

Barite is the primary ore for barium, and has varied industrial uses including paper, paint and glass manufacture as well medical radiology (as a dye) and in oil drilling.

Barites crystals found in Ohio can sometimes be massive in size.

Malachite

Malachite,Zaire

Malachite – sadly from Zaire and not Ohio

Photo By JJ Harrison (https://www.jjharrison.com.au/) – Own work, CC BY-SA 3.0,https://commons.wikimedia.org/w/index.php?curid=7515677

Typically found in botryoidal, stalagmitic, or fibrous masses, beautiful green malachite is collectible, and displayable.

It was a little hard to believe that malachite is found in Ohio, but according to the state it actually is present. Since it’s a copper carbonate hydroxide mineral it obviously needs copper to be present to form, and I did find a reference to a copper mine in Cuyahoga county.

Pyrite

Pyrite snake concretion Ohio Shale Upper Devonian creek cut in Ross County, southern Ohio, USA

Pyrite

Photo By James St. John – Pyrite snake concretion (Ohio Shale, Upper Devonian; creek cut in Ross County, southern Ohio, USA) 8, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=84692435

Iron Pyrite, commonly known as “fool’s gold”, is metallic iron sulfide mineral found in over 88 Ohio counties, typically in Devonian or Pennsylvanian shales. Pyrite has been used as an ore for sulfur and a source of iron.

The most common sulfide mineral, pyrite can form form in extremely well-crystallized examples of cubes, pyritohedrons, and octahedrons.

Sphalerite

Sphalerite on dolostone Millersville Quarry, Sandusky County, Ohio

Sphalerite crystals atop sucrosic dolostone from Sandusky County, Ohio

Photo by James St. John – https://www.flickr.com/photos/jsjgeology/31282767801/, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=101721070

Sphalerite is a sulfide mineral that is an ore of zinc, cadmium, gallium, germanium, and indium. It has a wide variety of colors including light/dark brown, red-brown, yellow, red, green, light blue, black, and colorless. It occurs in the Findlay Arch area, near Serpent Mound, and in Eastern Ohio.

Smithsonite

example of smithsonite

Illustrative example of smithsonite – sadly, not from Ohio. This example is from the Kelley Mine in Soccorro County, New Mexico.

Photo by Bureau of Mines – http://libraryphoto.cr.usgs.gov/cgi-bin/show_picture.cgi?ID=ID.%20BOM%20Mineral%20Specimens%20016, Public Domain, https://commons.wikimedia.org/w/index.php?curid=1825549

Smithsonite is named after English geologist and chemist James Smithson. Also known as zinc spar, this form of mineral zinc carbonate is a variably colored trigonal mineral.

Special Mention: Fossils

While not minerals, it would be unforgivable to not mention Ohio’s rich treasure trove of minerals. The greater Cincinnati area (which includes parts of northern Kentucky and southeastern Indiana) sits atop what is known as the Cincinnati Arch, the eroded remains of a mountain range from Michigan to Alabama that was thrust up by collision of two ancient continents. The arch sank beneath a series of shallow inland seas filled with marine life ending up as deposits of fossils in what is known to geologists as the Cincinnatian Epoch.

The region is famous for a wide variety of marine fossils, but particularly Trilobites, a now extinct member of the arthropod family.

Phacops rana,Silica,Ohio

Example of Ohio Eldredgeops rana fossil

Photo by Daderot – Own work, CC0, https://commons.wikimedia.org/w/index.php?curid=83993913

Graftonoceras – limonite-stained external mold of nautiloid in dolostone

Photo By James St. John – Graftonoceras fossil nautiloid (Lockport Dolomite, Middle Silurian; Coldwater, southern Mercer County, western Ohio, USA), CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=36833417

Graftonoceras fossil nautiloid (Lockport Dolomite, Middle Silurian;Coldwater,southern Mercer County).
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Ever Popular Ever Beautiful Rose Quartz

Of all the variety of minerals and crystals, perhaps the most beloved and widely collected is quartz. Named from the old Saxon word querklufterz meaning ‘cross vein ore’, it is popular with collectors, healers, artists, craftsmen, and people just looking for beautiful jewelry or items to display in their home. Quartz has something for everyone: a startling variety of colors; beautiful geometrically precise crystals; crystals ranging in size from druzy to monumental; strange and fantastical interior minerals such as hematite. Quartz is also the most abundant mineral on our planet.

Pure quartz is a colorless form of silicon dioxide, but there is a wide variety of both colored quartz and minerals that are not commonly understood to be a variety of quartz, such as amethyst, citrine, praseolite, chalcedony, and herkimer diamonds. Many of these varieties derive their color from impurities. Amethyst, for example owes its purple color to a combination of iron impurities trapped in the crystal along with holes in its structure from missing elections. Gray quartz similarly has missing electrons, but instead of iron impurities, it has aluminum impurities. Aside from color, quartz is usually grouped based on the size of the size of individual crystals or grains. If the individual crystal is too small to see using the naked eye, then the crystal is referred to as being cryptocrystalline quartz. If you can use your unaided eye to see the crystal, then it is classified as macrocrystalline quartz.

Rose quartz is a popular macrocrystalline form of quartz best know for its solid masses, beautiful glassy luster and translucent, even, milky pink color. The source of the color is still not well understood. One theory argues that it is due minor impurities such as titanium, manganese or even colloidal gold. The other theory argues that color comes from microscopic mineral fibers of dumortierite inside the rose quartz. Some examples exhibit asterism – a star effect when looking at the mineral from a particular angle when light is shone upon it. In general, rose quartz does not form crystals like you see with other forms of quartz.

Its delicate color has inspired art in other mediums including this glass vase on at the Chrysler Museum, and has its own color listing in the Pantone color library. Man has worked with the material back into antiquity. Beads made of the material have been discovered in the near east. The Chinese, particularly during the Qing dynasty, used the material for carvings. It was crafted in Latin America, and India as well.

Rose Quartz Vase

18th Century, Chinese, Qing Dynasty

Rose Quartz and Gold Double Bird Pendant
8th–12th century Coclé (Macaracas)

From Panama

Dagger (Jambiya)
18th century
Indian, Mughal

Steel, ivory (walrus), silver, ruby, rose quartz

Rose quartz was believed by the Romans, Egyptians and Greeks to be a useful talisman, and the Romans carved it into ownership seals. It was known during medieval times as the love stone, and the Chinese valued it’s properties in the practice of Feng Shui. Given the strong and ancient beliefs that the stone had special properties , it is no surprise that a strong literature has arisen around the material in modern times discussing metaphysical, healing, Reiki, or other spiritual properties of the material.

Ring, filigree with rose quartz

Greek or Roman, from Cyprus

Rose Quartz continues to inspire people, even in modern times. It’s a name given to a character in the Cartoon Network show Steven Universe. In the show, Steven is half-human and half “gem”, a type of ageless alien warrior that project human like forms from the gemstones in their core. Steven inherits his half “gem” lineage from his full-gem mother, Rose Quartz.

Rose Quartz (right), Steven Universe’s mother from the Cartoon Network show “Steven Universe”

By Hilary Florido, Katie Mitroff and Rebecca Sugar (authors); Cartoon Network / Time Warner (copyright owners) – Own screenshot, Fair use, https://en.wikipedia.org/w/index.php?curid=50775788

Rose quartz is found today in southern Africa (Madagascar, South Africa, and Namibia) as well as Brazil (Bahia and Minas Gerais) and interestingly, South Dakota.

There is a second variety of quartz sometimes grouped under the name rose quartz, but also referred to as pink crystalline quartz or crystalline rose quartz or even just pink quartz. This variety is much rarer, forms beautiful crystals and the best examples hail from the Minas Gerais region of Brazil.

For your own rose crystal display piece or healing stone check out Georarities’ selection of rose quartz crystals for sale.

Flower holder with pomegranate

18th Century, Chinese, Qing Dynasty

Snuff Bottle with Floral Design
late 18th century
China, Qing Dynasty

Aquamarine with Rose Quartz Topper

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Beautiful Collectible Kentucky Agate

Borden Formation Lower Mississippian Eastern Kentucky Agate

Located in east-central near the town of Irvine is Knob’s Region, a “u” shaped arc extending for nearly 230 miles that is home to Kentucky agate, the officially designated state rock of the Commonwealth of Kentucky. Highly collectible, Kentucky agate is a beautiful form of agate particularly known for it’s deep red and black hues.

Agate is typically a chalcedony (silicon dioxide) variety of fine or microcrystalline quartz nodule or concretion that may contain banding, mottled or variegated coloring. While most agates from in igneous rocks, Kentucky agate is one of the rare exception that forms in sedimentary rocks, a list which also includes Montana agates and Fairburn agates in the Black Hills.

Kentucky agate tends to be prone to cracking, finding quality specimens without cracks tends to be a challenge, making specimens used in jewelry that are free of the cracks particularly prized, collectible and expensive.

We offer a wide variety of both agates and Kentucky agates for sale on our website, and we have an even wider selection in our studio/gallery including the beautiful black and red pendant below which is our own creation .

Rare Red on Black Kentucky Agate Pendant with Dragon on Reverse KYA2-#KYA2-1

Kentucky Agate is often used in jewelry such as this beautiful Red on Black Kentucky Agate Pendant. Note the micro cracks in the stone which is common with this variety of agate due to how it forms.

Agate nodule displaying reds, blacks and yellows. Note the micro cracks. From Estil or Powell County, Kentucky. Photo By James St. John – Agate (Borden Formation, Lower Mississippian; eastern Kentucky, USA) 6, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=82926380

Agate nodule from Kentucky with dark reds, orange, black and whites. Photo by James St. John – Agate (Borden Formation, Lower Mississippian; eastern Kentucky, USA) 12, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=82926386

Agate nodule from Kentucky, USA, photo By James St. John – Agate (Borden Formation, Lower Mississippian; eastern Kentucky, USA) 13, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=82926390

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Short Crystal: Quartz and the Fossilized Bird

Photograph of the holotype of Zhouornis hani, a type of Enantiornithes

A recent study in Frontiers in Earth Science reveals that researchers discovered quartz crystals in the stomach of a bird that lived alongside the dinosaurs. The bird, a member of the Enantiornithes clade of fossil birds, appeared to be a sensational discovery, as previously there had never been a find which preserved any traces of food in the fossils stomach which would clue researchers in to the diet of the animal. Many modern birds have what’s called a gizzard, a thick and muscular portion of the stomach used to help digest food. Often birds swallow small stones know as gizzard stones, which make their way to the gizzard itself where it helps to crush tough or difficult to digest food. These stones are know as gastroliths and have been found in some dino and bird fossils providing hints as to the diet of those animals. The presense of stones in the stomach, though isn’t defiinitive as to the purpose of the stones. There are some modern birtds of prey that swallow rocks to help move material through their digestive tract, cleaning it out, and it’s hard to differentiate between a gastrolith and a gastrolith that is a gizzard stone without knowing anything about the diet and habits of the animal using the stone. In the end, the reesearchers determined that the quart material found where the birds stomach would have been probably was a gastrolight at all. After exposing the supposed gastroliths to X-rays and a scanning electron microscope it was determined that the rocks were actually chalcedony crystals, quartz that grew in sedimentary rocks. There is evidence of chalcedony crystals forming with a clamshell, or replacing minerals in fossil bones. Furthermore, the crystals in this case were all connected in a thin sheet rather than separate rocks. The rocks were also much larger than would be expected of rocks swallowed by a bird that size. In the end there just wasn’t enough evidence, and some negative evidence against the idea that the rocks were in the birds stomach. Just goes to show, never count your gastroliths before they’s been swallowed.

We don’t have any examples of Enantiornithes, but you can check our our collection of fossils for sale here.

Top image is a photograph of the holotype of Zhouornis hani, a type of Enantiornithes,
By Yuguang Zhang, Jingmai O’Connor, Liu Di, Meng Qingjin, Trond Sigurdsen, Luis M. Chiappe​ – https://peerj.com/articles/407/, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=33060650