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Curious, Glittering Goldstone: Mineral, Crystal, Something Else Altogether?

Goldstone glass under magnification

Goldstone. You know it, that gorgeous with a glittering star field that comes in blue, red, green or purple. It’s used for jewelry. It looks wonderful on your desk as a paperweight, or on a shelf as an eye-catching display object. Kids love it because of the sparkles. Adults love it too – take a deep look into a dark blue example and after a few moments you lost in what feels like the star field in the opening of Star Wars. But what exactly is Goldstone, and were does it come from? What mine do they dig the stuff out of?

Well, as it turns out, it comes from no mine. Even though it sure likes an amazing example of mother nature’s artistry, perhaps helped along with human assistance and a tumbler, it is actually man made. That’s right, it is synthetic. But not synthetic in a bad way, and certainly not synthetic in the modern sense such as with Ruby, which is created by fusing potash alum at a high temperature with a little chromium as a pigment. No, Goldstone is no lab or factory born. It’s birth is traced to the hand of the artist and artisan. But before we look at origins, let’s look at exactly what Goldstone is.

What is Goldstone?

Goldstone is form of man-made glass. It has a glittering, metallic character luster caused by flat faced and highly reflective inclusions of copper. The luster is caused by heating molten glass to the temperature necessary to dissolve copper oxide granules added to the molten glass. The melt is then cooled slowly allow the copper ions to grow into uniformly dispersed octohedral shaped crystals. The size of the copper crystals formed is directly related to the length of time taken to coll the melt. The longer the cooling, the larger the crystals. It is these copper crystals that creates the glittering luster.

But wait, you ask. What make gives the goldstone it’s red, or blue, or green, or purple color in which the copper stars are fixed? Well, the answer to that differs with each color of goldstone. Glass itself is typically colorless, and goldstone is no exception. Red goldstone is red because of reflection off the copper crystals. Blue, green, and purple goldstone use metals other than copper, but the background color doesn’t come from the metal, but rather from the addition of other elements to the glass itself. The blue in blue goldstone is caused by the addition of cobalt to the glass, green from the addition of chromium, and purple from the addition of manganese. Goldstone without copper is easier to work with when reheated, because of less stringent reduction requirements and higher melting points of manganese and cobalt.

Regardless of the metal used to create the particular color of the star field pattern, the glitter effect is intensified when a piece of goldstone is moved under light, when a lighting source is moved over the goldstone, or when the observer is in motion relative to a piece of lighted goldstone. If that sound technical, then think of it like this. A lighted piece of goldstone gets a whole lot glitterier if either you move it, you move yourself, or you move the light.

History of Goldstone

Goldstone dates as far back as the period between the 12th and 13th centuries A.D., the earliest known goldstone object being an amulet excavated in Iran with an inscription dedicating it to one of the rulers of Syria during that period. It was being manufactured in Italy by the 17th century, in Murano and Venice. The Motti family of Venice was granted an exclusive license to manufacture the material by the Doge (think “Duke”, they both originate from the same word) of Venice. The Chinese were making goldstone around the same time as the Italians with bottles made of the material by the Imperial Workshop handed out by the Qing Emperor’s court as gifts and rewards.

Goldstone is actually a more recent name for the material. An earlier common name for it aventurine glass, based on the Italian “avventurina” meaning “by chance” or “accident” in reference to the tale that the discovery of how to make the material was an accident. Goldstone should not be confused with the mineral aventurine, which is a feldspar or quartz with a mica inclusion that can also be glittery. In point of fact, the mineral was named after the goldstone because it’s glittery luster was reminiscent of of goldstone.

Party Tricks with Aventurine

So the heading is a bit of joke – there will be no party tricks discussed here. Instead let’s talk a little bit more about the name aventurine, the early name for goldstone. Besides gifting it’s name to the natural mineral aventurine, goldstone has lent it’s original to several technical terms used to describe that glittery loveliness goldstone is in possession so much of.

First is the term “aventurescence” which refers to the phenomena that occurs when a material with light-reflecting particles that produce a sparkly or glittery luster.

Then we have the term “aventurescent” which describes (also see the definition of adjective) materials that exhibit the phenomena of aventurescence. Usage examples include: aventurescent quartz, aventurescent feldspar, aventurescent iolite, and aventurescent soda pop. Actually that last item is joke, but soda pop beside shimmery and bubbly right after pouring does remind one of goldstone, well, a bit.

Cousins of Goldstone and Other Curious Facts

There are other types of glass that have some similarity to goldstone. For example, there is transparent red copper ruby glass and also opaque “sealing wax” purpurin glass, all of which have beautiful reddish colors of which are created by colloidal copper. The key difference among these is the size of the copper crystals. Goldstone has macroscopic (large) reflective crystals; purpurin glass has microscopic (small) opaque particles; copper ruby glass has submicroscopic (very small) transparent nanoparticles.

The outer layers of a batch of goldstone often has a duller color and less glittery goodness, characteristics usually dues to poor crystallization which decreases the size of the reflective copper crystals and makes the surrounding glass more opaque with non reflective particles. This may also be due to partial oxidation of the copper which may lead the crystals dissolving leading to a transparent blue-green glass.

Sometimes goldstone only displays the glittering effect from two directions rather than from any vantage point.

Goldstone is actually popular for cutting jewelry. As rough pieces, it is usually sold as broken chunks and as slabs suitable for cutting cabochons. Smaller pieces might be rock tumbled, while larger chunks might weight over 50 pounds. A single batch of goldstone usually weighs in at 100 pounds or more, before being cut into smaller chunks. The quality of the goldstone due to variability from the manufacturing process will dictate the end use.

Metaphysical, Spiritual, and Healing Properties of Goldstone

Even though goldstone is synthetic, many believe it has spiritual or metaphysical properties, and can be used in physical healing. The specific properties and effects of the goldstone vary depending on who you consult, and their particular perspective. One thing is certain, contemplating the start field of a beautiful example of goldstone can be a calming and meditative experience!

We sell goldstone. Check out our selection, or visit us in-person.

Top photo depicting a piece of ‘red’ or ‘brown’ Goldstone glass under magnification to show the crystals inside – by Albionfireandice – website, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=104498606

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The Uncertain Future of Afghanistan’s Mineral Wealth

Corundum

Poor Afghanistan. It is the country that never seems to catch a break. Remote, poor, land-locked, and yet highly strategic because of its position as the gateway to India and its position athwart the ancient silk road trade route to China, it has seen armies pass through from Alexander the Great to the Moghuls (think the creators of the Taj Mahal), to the British and Russians, and finally the Soviet and Americans.

Map of Mineral Resources of Afghanistan

Afghanistan Mineral Resources

Photo By This file was contributed to Wikimedia Commons by National Archives at College Park – Cartographic as part of a cooperation project. The donation was facilitated by the Digital Public Library of America, via its partner National Archives and Records Administration.National Archives Identifier: 159081989Source record: http://catalog.archives.gov/id/159081989DPLA identifier: a982bb69e64e77d42e7d7f8e0a1c5f33, Public Domain, https://commons.wikimedia.org/w/index.php?curid=96782925

One ever-constant bright spot for the nation has been the enormous mineral wealth it sits above. A massive upheaval about 40 million years ago between the Indo-European, the African, and Asian plates created the towering mountains upon which the nation sprawls. This also created a wide variety and enormous quantity of mineral wealth, particularly in the north and northeast of the country All told there are over 1,400 mineral fields encompassing barite, chromite, coal, copper, gold, iron ore, lead, natural gas, petroleum, precious and semi-precious stones, salt, sulfur, lithium, talc, and zinc, rare earth minerals, and high-quality emerald, lapis lazuli, red garnet, tourmaline, turquoise and ruby just to name a few examples. This enormous wealth has been well know for over a century from surveys conducted by the British and Russians. During their occupation the Soviets conducted their own survey. Most recently, a United States Geological Survey estimate prepared after the overthrow of the Taliban that there was perhaps a trillion dollars worth of mineral wealth in Afghanistan.

Industrial Minerals

Madan Turquoise Mines

An early turquoise mine in the Madan village of Khorasan

Photo by Major Henri De Bouillane de Lacoste (tr. by J. G. Anderson) – “Around Afghanistan” as digitised by the Internet Archive’s text collection., Public Domain, https://commons.wikimedia.org/w/index.php?curid=3850890

The mineral wealth can be divided into industrially useful and specimens & gemstones. Just in Baghlan Province one finds important deposits of clay, bauxite, gypsum, limestone, and coal. Clay in particular has been used since ancient times. Other industrially useful minerals include chromium, mercury, copper, gold, silver, iron ore, lead, tungsten, zinc, lithium, beryllium, cobalt, marble, sulfur, tin and talc. Perhaps the world’s largest copper lode exists in Aynak.

Doost marble Factory

An Afghan Marble Factory

Photo by USAID Afghanistan – 100525 Hirat Marble Conference 133, Public Domain, https://commons.wikimedia.org/w/index.php?curid=15375462

Green Ceramic Tile

Green Tile with Star Design, 12th–13th century, Earthenware; molded decoration, monochrome glazed, Attributed to Afghanistan

Gem Producing Regions

Afghanistan is particularly noted for it’s rich gemstone wealth. Lapis Lazuli, Kunzite, Morganite, Emerald, Aquamarine, Tourmaline, Beryl, Spinel, Sapphire, Topaz, Fluorite, Garnet, Corundum (Ruby), and Green Serpentine are all present. Indeed, the Black Prince’s Ruby and the “Timur ruby” in the British Crown Jewels (both actually Spinel and not Ruby) are both believed to have originated in or near Afghanistan. Most recently, and perhaps controversially Hiddenite (or “Hiddenite-like”) has been discovered.

There are four main gem-producing regions: the Panjshir Valley for emeralds, the Jegdalek area for rubies and a range of fancy colored and blue sapphires, Badakhshan for lapis lazuli, and Nuristan for a wide variety of semi-precious gems including as tourmaline, kunzite, aquamarine, spodumene and beryl.

The Panjshir emerald deposit may refer to the ‘smaragdus (green stones) from Bactria’ in Pliny’s in his ‘Natural History’, written in the first century AD. The emeralds occur at altitudes of between 3000 and 4000 meters. The clarity of these emeralds rivals that of the world-famous Colombian emeralds. The remote and inaccessible Panjshir valley, is also the home of the Northern Alliance – the main Afghan resistance to both the Soviets and the Taliban in the 1970 – 2000s. The same inaccessible terrain makes extracting the emeralds a challenge.

Beryl

Beryl (Var.: Emerald) Locality: Panjsher (Panjshir) Valley, Hessa-e-Say District, Panjshir (Panjsheer) Province, Afghanistan

Photo by Rob Lavinsky, iRocks.com – CC-BY-SA-3.0, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=10135249

Jegdalek Gandamak rubies are mined in Kabul Province from Proterozoic calcite-dolomite marble bed between 500 and 2000 m thick in a regionally metamorphosed marble cut by Oligocene granitic intrusions. This mine was worked to provide marble for the Taj Mahal – but it is uncertain whether rubies were actively mined at that time. Jegdalek rubies range from nearly colorless to deep red and purplish red with strong UV fluorescence. True rubies form about 15 % of production, along with pink sapphires (75 %) and blue sapphire (5 %), and 5 % mixed blue and red-to-pink corundum.
Clean faceting quality rubies from this mine are said to match the very best in the world.

Corundum

Corundum Locality: Jegdalek (Jagdalek; Jagdalak; Jagdalik) Ruby Mine, Sorobi District, Kabol (Kabul) Province, Afghanistan 

Photo by Rob Lavinsky, iRocks.com – CC-BY-SA-3.0, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=10448845

Afghanistan is world famous for its lapis lazuli, a rock composed of the feldspathoid minerals lazurite, hauyne, nosean and sodalite, with other minerals including calcite and pyrite and lesser amounts of diopside, amphibole, feldspar, mica and other silicates. Lapis from Badakhshan in the north of the country is still regarded as the world’s premier source in terms of quantity and quality. The name derives from a mixture of Latin and Persian: the Latin ‘lapis’, meaning ‘stone’ and the Persian ‘lazhward’ meaning ‘blue’. Then material is used to make beads, boxes and other decorative articles, often carved into figurines and is popular for men’s jewelry.

Lapis is mined on the right bank of the Kokcha River in Badakhshan in an area known as the ‘Blue Mountain’ in skarn lenses 1–4 m thick in marble. At one time there were as many as seven lapis mines there is only one, the Sary-Sang deposit at an elevation of around 3500 m where, on because of low winter temperatures, mining occurs only between
June and September.

Lapis Lazuli

The highest quality lapis lazuli in the world is from northeastern Afghanistan (northern Kuran Wa Munjan District, southern Badakhshan Province)

Photo by James St. John – Lapis lazuli (lazuritic gneiss) (Sar-e-Sang Deposit, Sakhi Formation, Precambrian, 2.4-2.7 Ga (?); Sar-e-Sang Mining District, Hindu-Kush Mountains, Afghanistan) 1, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=83302689

Lazurite

Lazurite, Pyrite, marble Locality: Sar-e-Sang District, Koksha Valley (Kokscha; Kokcha), Badakhshan (Badakshan; Badahsan) Province, Afghanistan. A well-formed euhedral crystal of lazurite (lapis lazuli) – not to be confused with lazulite

Photo by Rob Lavinsky, iRocks.com – CC-BY-SA-3.0, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=10175015

Afghanite

Afghanite on Calcite, Koksha Valley, Badakhshan, Afghanistan, Asia

The fourth major gemstone region is Nuristan on the eastern side of Afghanistan bordering Pakistan, an area dotted with high mountains cut by numerous steep-sided valleys. The region is notable for its pegmatite fields, a late-stage crystallisation from molten rock, hosting a wide variety of minerals and gems commonly of unusual size and quality. Gem-quality tourmalines in a wide range of colors from pink though pale blue, indigo blue (indicolite), green, and emerald green. In addition, rare two-colored stones of green-pink and blue-green are much sought after. The crystals are beautifully formed, elongate with a distinctive ‘rounded triangular’ cross-section.

Elbaite

Elbaite Locality: Paroon Mine, Darra-i-Pech (Pech; Peech; Darra-e-Pech) Pegmatite Field, Nangarhar (Ningarhar) Province, Afghanistan

Photo by Rob Lavinsky, iRocks.com – CC-BY-SA-3.0, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=10448930

History

Some of the world’s oldest mines are believed to be in Afghanistan. Production in antiquity focused on precious stone production as well gold and silver extraction. Lapis lazuli was produced in the region of Badakhshan as early as 8000 B.C. Lapis was traded to the ancient Egyptians, Sumerians, Assyrians, Akkadians, Babylonians to be made into amulets, seals and other objects. The Aynak copper mine has been in use for at least two thousand years based on the coins and tools found on the site. Afghan ruby and spinel is mentioned in writing of many travelers from the Muslim world from the mid-900s onward. Rich iron, metal, gold, copper and silver deposits are indicated by a strong metal working tradition, and the deposits of lapis, marble, alabaster and other materials led to a strong stone carving tradition.

Gold and Turquoise Shoe Buckle

Shoe Buckle in the Shape of a Recumbent Ram, Bactria, 1st century B.C.–1st century A.D. Gold inlaid with turqoise.

Khyber Knife

Khyber Knife, made of steel and iron, Afghanistan, 18th – 19th centuries. Afghanistan has significant iron deposits.

Seated Alabaster Figure

Bronze Age Seated female, ca. late 3rd–early 2nd millennium B.C., Steatite or chlorite, alabaster, Bactria-Margiana

Today’s Challenges

Capitalizing on its sovereign mineral wealth has always been challenging for Afghanistan. Corruption, civil war, occupation, have meant problems extracting, and transport minerals, and great difficulty in the wealth being used to improve the well-being of the population. Mineral extraction, particularly in the high mountain mines remains exploitative and dangerous. These challenges are compounded now by the renewed takeover of the country by the Taliban. Traditionally, whichever party ruled the nation tried to exert control over the mineral wealth, and the Taliban are no exception. There is discussion of the government imposing new taxes on the mineral extractors, transporters, and exporters. Will any of the taxes make their way into the common good? Will those who labor at the bottom the industry benefit? Will the money simply support the Taliban? Will the endemic corruption inhibit or expedite the mineral extraction? All of these questions remain to be answered.

In addition to all these factors, Afghanistan is now the subject of new geo-strategic maneuvering. In the wake of the U.S. withdrawal and the collapse of the Republic of Afghanistan, new players are angling for power and influence to exploit the mineral wealth. Players like Iran, and Russia are making moves to strengthen their hand with the Taliban, and the discovery of vast deposits of rare earth mineral (in reality not terribly rare, but that’s another discussion entirely) and the newly recognized importance of the lithium deposits for use in electric car batteries has led to keen interest and competition by the Chinese in and Afghanistan. How this all plays out remains to be seen, but unfortunately it is most likely that little will change for the common laborer working in the mines of Afghanistan.

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Rare Jade Artifact Up for Auction – the Jade Seal of Emperor Qianlong

Emperor- Qianlong

It’s not often in Geology that you have an opportunity to personally link an item to a historical figure but thanks to Freeman’s auction house we can tie a beautiful piece of jade to one of the later Qing Dynasty emperors. Little did the Qianlong Emperor (born Aisin Gioro Hongli) and sixth emperor of the last Chinese imperial dynasty suspect one of his personal items would appear in an internet auction catalogue, but life is stranger than fiction. The item for sale is a gorgeous pale and luminous high relief carved jade seal in a celadon white tone. The carving depicts three qilong (unicorns) which are symbols of good luck among carved scrolling clouds which likely refers to the Chinese saying “Canlong jiaozi”, which may be translated as “The Eastern [blue] dragon teaching his son[s]”, probably referring to the personal situation of the emperor.

Jade is a traditional carving material in China. In ancient days in China jade was symbolized the inner beauty within humans. This certainly isn’t the first jade imperial seal. The first Chinese emperor, Qin Shi Huang, created the first Imperial seal, in 221 B.C., also of Jade. By the time of the Ming dynasty (starting in 1368) the first imperial seal was lost. Until the Ming dynasty seals were typically reserved for Imperial use. A Chinese seal (印章 yìnzhāng) is a device used to mark important documents, pieces of art, contracts, or any other item that requires a signature – in effect similar to a signet ring or in modern times an ink signature stamp. These seals were usually carven stone, but sometimes were made of wood, bamboo, bone, or ceramic. They would be dipped in either red ink or cinnabar paste.

View a video of the seal below or visit the Freeman auction site to learn more about the seal.

Top image

We may not have any imperial seals, but we have plenty of jade for sale. Check out our selection of Jade. If you don’t see something that tickles your fancy, contact us as we only post only a portion of our inventory online.

The Qianlong Emperor in court dress. Top image by Giuseppe Castiglione – Palace Museum, Beijing, Public Domain, https://commons.wikimedia.org/w/index.php?curid=15172620

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The Black Diamond, an Engima Weighing 555.55 Carats

Black Diamond

A gigantic black diamond, certified by Guiness as the world’s largest cut diamond is for sale through Sotheby’s auctions. Weighing in at a whopping 555.55 carats, the carbonado piece has 55 cuts and is heavier than its rivals the Great Star of Africa and the Golden Jubilee. The typical diamond is an uncovered kimberlite rock that was formed quite deep with the earth. Carbonado diamonds, one of the toughest of natural diamonds, however, are found in alluvial, sedimentary deposits. Lead istotope analyses of carbonados suggest their crystallization about 3 billion years ago, but this poses a paradox as the material carbonado is typically found is much younger than that. This paradox and a lack of mantle minerals often found in non-carbonado diamonds has lead some believe that carbonado has an extraterrestrial origin. In fact Sotheby’s suggest this hypothesis in their auction listing.

Check out Sotheby’s video of the the Enigma above or view their auction listing.

We may not have any black diamonds for sale, but we have plenty of gemstones and lapidary material. Don’t see exactly what you are looking for? Contact us as we make only a small selection of our inventory available online.

Top Photo is the Million Dollar Rarest Natural Black Diamond known as “shaan-e-kolkata” with a weight of 121.32 carats (24.264g) good round-cut presently in India.It’s certified by Golconda Institute of Diamonds, Hyderabad on 25th May 2012, an issued Certification of Authenticity by Mr. Imran Shareef (Certified Diamond Grader GIA New York, USA). Currently owned by Prem Singh from West Bengal,India. Photo by Trishtha – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=35937431

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New Miocene Fossil Find in Australia

Fossil Fern

A spectacular new fossil trove has been reported in New South Wales, Australia. Located in the Central Tablelands regions, about 25 miles from the 19th century gold rush town of Gulgong, and named McGraths Flat after the person who discovered the fossil cache, the site is a window into the wetter and forest dominated past of Australia.

The fossil cache includes thousands of beautifully preserved specimens of flowering plants, ferns, spiders, insects and fish dating to the Miocene (23.03 to 5.33 million years ago) era. Climactic upheaval during the Miocene dried the rainforests that once covered Australia. At the time of the fossil cache’s formation the rainforest that had once covered the site had changed into temperate forest around a small lake. A fine goethite (an iron hydroxide mineral) matrix acted to help preserve plants and insects in the water. A diverse array of flowers, ferns, arachnids, insects and other soft bodied animals have been found in the fossil cache.

Image is illustrative of fossilized fern Dennstaedtia americana. Image by James St. John – https://www.flickr.com/photos/[email protected]/39373225554/, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=97215903

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Simply Brilliant – An Exceptional Collection of Fine Jewelry with Outstanding Stones and Crystals

Cincinnati Art Museum Modern Jewelry Exhibit 1960s-1970s

The Cincinnati Art Museum has a new exhibit running through February 6th titled “Simply Brilliant: Artist-Jewelers of the 1960s and 1970s”. This exhibition of approximately 120 explores the international renaissance in fine jewelry in the 1960s and 1970s and features  the work of independent jewelers such as Andrew Grima, Gilbert Albert, Arthur King, Jean Vendome and Barbara Anton along with work created for Bulgari, Cartier, Boucheron and other major houses drawn from one of the most important private collections in the world, assembled by Cincinnatian Kimberly Klosterman.

Andrew Grima (British, b. Italy, 1921–2007), Brooch, 1969, gold, watermelon tourmaline, diamonds, Courtesy of the Cincinnati Art Museum, Collection of Kimberly Klosterman, Photography by Tony Walsh
Andrew Grima (British, b. Italy, 1921–2007), Brooch, 1969, gold, watermelon tourmaline, diamonds, Courtesy of the Cincinnati Art Museum, Collection of Kimberly Klosterman, Photography by Tony Walsh

The exhibition is accompanied by a full color illustrated catalogue and includes essays by some of the most important scholars in the field. Biographies of each designer/house represented are paired with full color images, extended text for a select number of highlighted pieces and an appendix of maker’s marks.

Jean Vendome (French, 1930–2017), Collier Veracruz (Veracruz Necklace), 1972, white gold, platinum, amethyst, diamonds, Courtesy of the Cincinnati Art Museum, Collection of Kimberly Klosterman, Photography by Tony Walsh

The individual makers represented in the exhibition referred to themselves as artists first, jewelers second, approaching their work as a modern art form. Largely utilizing yellow gold and incorporating both precious and semi-precious gems, and inspired by nature they focused on organic forms, favored abstract shapes and concepts related to space-age trends. Using unconventional materials such as coral, shell, geodes and moldavite bringing unrivaled texture to their jewelry. Theirs was a style that was appreciated by individuals who were looking for something different in an era when different was best.

Chopard (Swiss, est. 1860), Alexandra Watch, circa 1971, gold, diamonds, lapis lazuli, Courtesy of the Cincinnati Art Museum, Collection of Kimberly Klosterman, Photography by Tony Walsh

The exhibition is free and located in the Vance Waddell and Mayerson Galleries (Galleries 124 & 125), and is absolutely outstanding. We recommend you take advantage of the opportunity to see these pieces while you can.

The Cincinnati Art Museum is open 11am – 5 pm Tuesday – Sunday except for 11 am – 8 pm on Thursdays. Click here to for more information about the exhibit and the Cincinnati Art Museum.

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Gorgeous Yellow Brucite Crystal

Yellow brucite (4.0 × 3.0 × 2.5 cm) from Killa Saifullah, Balochistan, Pakistan.

Brucite is the mineral form of magnesium hydroxide named in 1824 by François Sulpice Beudant for its discoverer, American minerologist and chemist Archibald Bruce. Colors vary and may include light blue, milky white, or lemon yellow. It crystals typically have a fibrous body what could be described as a chalky or pearly luster. The structure of the mineral is maintained only weakly, making the it fragile. It is also know for shearing into perfectly flat sheets due to its crystal cleavages laying parallel to their plates.

Brucite is common, but excellent examples are hard to come by. Notable finds include in Wood’s Chrome Mine in Lancaster County, Pennsylvania as well as in Baluchistan, Pakistan. Recently there was a major discovery of brucite yielding beautiful and rare yellow and lemon-yellow specimens, some of which are startlingly and gorgeously transparent. Because the mineral is so fragile it is usually mined by hand

Besides collecting it is used as a source of magnesium and in some flame retardantion applications.

View our collection of brucite available for purchase

Image Credit: Yellow brucite (4.0 × 3.0 × 2.5 cm) from Killa Saifullah, Balochistan, Pakistan. By Ivar Leidus – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=98529310

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Beautiful Green Dioptase / Schöne grüne Dioptase / 美しい緑の翠銅鉱

Dioptase Locality: Tsumeb Mine (Tsumcorp Mine), Tsumeb, Otjikoto (Oshikoto) Region, Namibia. Pristine and perfect all around. Erik Louw was a miner on the dioptase stope who traded extensively and accumulated one of the finest Tsumeb miniatures collections, purchased in entirety by the Sussmans in the late 1990's. 4 x 4 x 1 cm

Beautiful Green Dioptase

Dioptase is an unusual mineral that is highly desired for its intense Emerald green color.  It is a copper cyclosilicate mineral that varies from transparent to translucent.  Very popular with mineral collectors he can be cut into small gems are also ground up and used as a pigment for painting.  Dioptase typically forms as a secondary mineral and copper deposits created through the weathering and oxidation of the primary minerals in either limestone or calcite formations.  It may be associated with other cupric minerals like malachite, chryscolla, and azurite.  It is a trigonal mineral which forms six-sided crystals that termine in rhombohedra.

Dioptase is uncommon and usually found in desert regions . Within the United States, deposits are mostly restricted to the state of Arizona. Globally Kazakhstan and in particular the Tsumeb mine in Namibia produce some of the best examples of this mineral.  Dioptase is also found in Congo and then Argentina in South America.  Better examples of this mineral can be quite costly.

Dioptase with calcite and minrecordite - Tsumeb Mine (Tsumcorp Mine), Tsumeb, Otjikoto (Oshikoto) Region, Namibia (5.5x4cm)
Dioptase with calcite and minrecordite – Tsumeb Mine (Tsumcorp Mine), Tsumeb, Otjikoto (Oshikoto) Region, Namibia (5.5x4cm)Dioptase mit Calcit und Minrecordit – Tsumeb-Mine (Tsumcorp-Mine), Tsumeb, Region Otjikoto (Oshikoto), Namibia (5,5 x 4 cm)方解石とミンレコーダイトを含む翠銅鉱-ツメブ鉱山(ツメブ鉱山)、ツメブ、オシコト(オシコト)地域、ナミビア(5.5x4cm)By Didier Descouens – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=8876953

In modern times dioptase was discovered at the end of the 18th century in the Central Asian steppes in Kazakhstan. The Russian mineralogist’s who discovered it confused it four form of emerald.  Despite having a similar color to emeralds dioptase actually has different optical and physical properties which differ enough the gemologists can easily distinguish one from the other.  Dioptase has been discovered to have been used to decorate plaster statues dating back to before 7000 BC.

Dioptase dust is toxic due to its copper content an accidental ingestion can lead to serious problems. Jewelers and fasteners should wear protective masks and ideally use a glove box to avoid inhaling or ingesting particles during the cutting polishing and cleaning processes. Finish pieces however typically pose no hazard.  Because of the cleavage pattern impossible fractures dioptase is should usually be cleaned with a mild detergent warm water and a soft brush.  Dioptase in general tends to be very fragile and specimens should be handled with great care.

Dioptase, Baryte, Plancheite Locality: Kaokoveld Plateau, Kunene Region, Namibia Size: 3.8 x 3.1 x 1.4 cm. A little orange barite perched atop! The central dioptase is 1.3 cm and pristine. The one on the edge is larger, but incomplete at its edge.
Dioptase, Baryte, Plancheite Locality: Kaokoveld Plateau, Kunene Region, Namibia Size: 3.8 x 3.1 x 1.4 cm. A little orange barite perched atop! The central dioptase is 1.3 cm and pristine. The one on the edge is larger, but incomplete at its edge.Dioptase, Baryt, Plancheite Lokalität: Kaokoveld-Plateau, Kunene-Region, Namibia Größe: 3,8 x 3,1 x 1,4 cm. Ein kleiner orangefarbener Baryt thront oben drauf! Die zentrale Dioptase ist 1,3 cm groß und makellos. Der am Rand ist größer, aber am Rand unvollständig.翠銅鉱、重晶石、プランヘ石産地:ナミビア、クネネ地方、カオコベルド高原サイズ:3.8 x 3.1 x1.4cm。 小さなオレンジ色の重晶石が上に腰掛けています! 中央の翠銅鉱は1.3cmで手付かずの状態です。 端にあるものは大きいですが、端が不完全です。By Rob Lavinsky, iRocks.com – CC-BY-SA-3.0, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=10175913

Learn more about the physical characteristics and crystallography of dioptase at mindat.

We carry a selection of fine specimens of Tsumeb dioptase for sale. Click hear for more information.

Auf Deutsch – Schöne grüne Dioptase

Dioptase ist ein ungewöhnliches Mineral, das wegen seiner intensiven smaragdgrünen Farbe sehr begehrt ist. Es ist ein Kupfercyclosilikatmineral, das von transparent bis durchscheinend variiert. Sehr beliebt bei Mineraliensammlern kann er in kleine Edelsteine ​​geschnitten werden, die ebenfalls gemahlen und als Pigment zum Malen verwendet werden. Dioptase bildet sich typischerweise als sekundäres Mineral und Kupferablagerungen, die durch Verwitterung und Oxidation der primären Mineralien in Kalkstein- oder Calcitformationen entstehen. Es kann mit anderen Kupfermineralien wie Malachit, Chrysokoll und Azurit assoziiert sein. Es ist ein trigonales Mineral, das sechsseitige Kristalle bildet, die in Rhomboedern enden.

Dioptase ist ungewöhnlich und kommt normalerweise in Wüstenregionen vor. In den Vereinigten Staaten sind die Einlagen meist auf den Bundesstaat Arizona beschränkt. Weltweit produzieren Kasachstan und insbesondere die Tsumeb-Mine in Namibia einige der besten Beispiele für dieses Mineral. Dioptase kommt auch im Kongo und dann in Argentinien in Südamerika vor. Bessere Beispiele für dieses Mineral können sehr kostspielig sein.

In der Neuzeit wurde Dioptase Ende des 18. Jahrhunderts in den zentralasiatischen Steppen in Kasachstan entdeckt. Die russischen Mineralogisten, die es entdeckten, verwirrten es mit vier Formen von Smaragd. Obwohl Dioptase eine ähnliche Farbe wie Smaragde aufweist, weist sie tatsächlich unterschiedliche optische und physikalische Eigenschaften auf, die sich so stark unterscheiden, dass die Gemmologen sie leicht voneinander unterscheiden können. Es wurde entdeckt, dass Dioptase zur Dekoration von Gipsstatuen aus der Zeit vor 7000 v. Chr. Verwendet wurde.

Dioptasestaub ist aufgrund seines Kupfergehalts giftig. Eine versehentliche Einnahme kann zu ernsthaften Problemen führen. Juweliere und Befestiger sollten Schutzmasken tragen und idealerweise ein Handschuhfach verwenden, um das Einatmen oder Einnehmen von Partikeln während des Polier- und Reinigungsprozesses zu vermeiden. Endstücke stellen jedoch normalerweise keine Gefahr dar. Aufgrund des Spaltmusters sollten unmögliche Frakturen der Dioptase normalerweise mit einem milden Reinigungsmittel, warmem Wasser und einer weichen Bürste gereinigt werden. Dioptase neigt im Allgemeinen dazu, sehr zerbrechlich zu sein, und Proben sollten mit großer Sorgfalt behandelt werden.

Erfahren Sie mehr über die physikalischen Eigenschaften und die Kristallographie der Dioptase bei mindat.

Wir führen eine Auswahl feiner Exemplare der Tsumeb-Dioptase zum Verkauf. Klicken Sie hier für weitere Informationen..

日本語で -美しい緑の翠銅鉱

翠銅鉱は、その強烈なエメラルドグリーンの色のために非常に望まれている珍しい鉱物です。これは、透明から半透明まで変化する銅シクロシリケート鉱物です。鉱物収集家に非常に人気があり、小さな宝石にカットすることもできます。粉砕して、絵画の顔料として使用します。翠銅鉱は通常、石灰岩または方解石層のいずれかで一次鉱物の風化と酸化によって生成される二次鉱物と銅の堆積物として形成されます。マラカイト、クリスコラ、アズライトなどの他の第二銅鉱物と関連している可能性があります。菱面体で終端する6面結晶を形成する三方晶系鉱物です。

翠銅鉱はまれであり、通常は砂漠地帯で見られます。米国内では、預金は主にアリゾナ州に制限されています。世界的にカザフスタン、特にナミビアのツメブ鉱山は、この鉱物の最良の例のいくつかを生産しています。翠銅鉱は、南米のコンゴ、次にアルゼンチンでも見られます。この鉱物のより良い例はかなり費用がかかる可能性があります。

現代では、18世紀の終わりにカザフスタンの中央アジアの草原で翠銅鉱が発見されました。それを発見したロシアの鉱物学者は、それを4つの形のエメラルドと混同しました。エメラルドに似た色をしているにもかかわらず、翠銅鉱は実際には異なる光学的および物理的特性を持っており、宝石学者は簡単に区別することができます。翠銅鉱は、紀元前7000年以前にさかのぼる石膏像を飾るために使用されていたことが発見されました。

翠銅鉱の粉塵は銅含有量が原因で有毒であり、誤って摂取すると深刻な問題を引き起こす可能性があります。宝石商と留め具は保護マスクを着用し、理想的にはグローブボックスを使用して、切削研磨および洗浄プロセス中に粒子を吸い込んだり摂取したりしないようにする必要があります。ただし、仕上げ部品は通常、危険をもたらしません。劈開パターンが不可能なため、翠銅鉱は通常、中性洗剤の温水と柔らかいブラシで洗浄する必要があります。一般に翠銅鉱は非常に壊れやすい傾向があり、検体は細心の注意を払って取り扱う必要があります。

mindatで翠銅鉱の物理的特性と結晶学についてもっと学びましょう。

ツメブ翠銅鉱の厳選された標本を販売しています。 詳細については、ここをクリックしてください。

Top Image Credit: Dioptase Locality: Tsumeb Mine (Tsumcorp Mine), Tsumeb, Otjikoto (Oshikoto) Region, Namibia A startlingly sculptural specimen! Pristine and perfect all around. Erik Louw was a miner on the dioptase stope who traded extensively and accumulated one of the finest Tsumeb miniatures collections, purchased in entirety by the Sussmans in the late 1990’s. 4 x 4 x 1 cm Dioptase-Lokalität: Tsumeb-Mine (Tsumcorp-Mine), Tsumeb, Region Otjikoto (Oshikoto), Namibia Ein erstaunlich skulpturales Exemplar! Rundum makellos und perfekt. Erik Louw war ein Bergmann auf der Dioptase-Station, der ausgiebig handelte und eine der besten Tsumeb-Miniaturensammlungen sammelte, die Ende der 90er Jahre vollständig von den Sussmans gekauft wurden. 4 x 4 x 1 cm 翠銅鉱産地:ナミビア、ツメブ鉱山(ツメブ鉱山)、オシコト地方、ツメブ驚くべき彫刻標本! 手付かずで完璧です。 Erik Louwは、1990年代後半にサスマンによって完全に購入された、ツメブの最高のミニチュアコレクションの1つを幅広く取引し、蓄積した翠銅鉱の鉱夫でした。 4 x 4 x 1 cm By Rob Lavinsky, iRocks.com – CC-BY-SA-3.0, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=10109320

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Beautiful Bejeweled Amethyst’s History as an Art Medium

Amethyst intaglio portrait of Julius Caesar, Roman, 50-40 B.C.E.

The February birthstone is amethyst. A form of non-fluorescing hard stone quartz whose typically purple shading comes from irradiation of iron or transition element impurities, amethyst was once considered one of the cardinal, or most valuable, gemstones. Occasionally exhibiting secondary shades of blue or red, the beautiful stone is highly popular among mineral collectors, crystal healers, art lovers, lapidaries. While not considered as valuable as it once was due to recent discoveries of large deposits of the mineral, amethyst often produces stunning jewelry.

Traditionally most carved gemstones in the west are a form of quartz, the carving techniques adopted for quartz also apply to amethyst. Amethyst deposits have been found on almost every continent and it’s availability was a key factor in it’s popularity as a carving medium of artisans in antiquity. Deposits have been found in Brazil, Uruguay, Austria, Russia, Zambia, and Korea, as well the eastern and southern areas of the United States, including Texas, North Carolina, and the Lake Superior Region.

Amethysts was carved and treasured by cultures such as those of Japan, Iran, Greece, Rome, Egypt, the Anglo-Saxons and others. Different cultures each put their own spin on the importance, meaning and value of the stone. It was highly treasured by Russian Empress Catherine who sent thousands of miners into the Ural mountains seeking the gemstone. In ancient Rome, the purple color of the gem was associated with the purple color reserved for the elite and the emperor. The medieval Catholic church’s bishops prized amethyst’s color. The ancient Egyptians worked the material into amulets for protection against harm. Moses the prophet is said to have described amethyst as representing the spirit of god. The ancient Greeks believed the stone offered protection from drunkenness. The Tibetans created rosaries from the stone and considered it sacred to Buddha. Leonardo Da Vinci wrote that amethyst quickened intelligence and dissipated evil thoughts. The Anglo-Saxons fashioned beads, while was used for intaglio.

In this article we present a visual tour of the different ways amethyst has been used in art, both ancient, antique, and modern.

Amethyst intaglio portrait of Julius Caesar, Roman, 50-40 B.C.E.

Amethyst intaglio portrait of Julius Caesar, Roman, 50-40 B.C.E.

Byzantine Jeweled Bracelet of gold, silver, pearls, amethyst, sapphire, glass, quartz, 500-700 C.E.

Byzantine Jeweled Bracelet of gold, silver, pearls, amethyst, sapphire, glass, quartz
1st Century Greek or Roman Amethyst Oval

1st Century Greek or Roman Amethyst Oval

Frankish Disk Brooch, c. 550-650 B.C.E. with Amethyst Jewel

Amethyst, Copper, Gold and Silver Frankish Disk Brooch, 550-650 C.E.
American Brooch by Theodore B. Starr, 1900, Amethyst, Gold, Garnet, Enamel

Amethyst, Garnet, Gold and Enamel Brooch by Theodore B. Starr, American, 1900

Egyptian Amethyst Scarab, Middle Kingdom, ca. 1981–1950 B.C. The scarab beetle was a potent symbol of creation and regeneration among the ancient Egyptians.

Egyptian Amethyst Scarab, Middle Kingdom, 1981-1950 B.C.E.
Chinese Amethyst Qing Dynasty Seal, Late 19th-early 20th Century

Chinese Qing Dynasty Amethyst , Late 19th – Early 20th Century

Chinese Qing Dynasty Snuff Bottle of White, Green and Brown Jadeite with Amethyst Stopper, Qianlong Period (1736-1795)

Chinese Qing Dynasty Snuff Bottle of White, Green, and Brown Jadeite with Amethyst Quartz Stopper 1736-95
Spanish Clip Earrings, mid-19ths Century, Gold, Metal and Amethyst

Mid-19th Century Avant-Garde Spanish Clip Earrings, Amethyst, Silver, Metal

We may not have antique carvings, but you can check out our lovely collection of amethyst for sale.