• Created By : 14-Dec-2014
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Indicolite tourmaline, Karibib, Namibia, 4.2cm

Indicolite is the indigo- or neon-blue colored variety of elbaite, which is one of 14 tourmaline mineral species. The term "indicolite" comes from the Latin word for the "indicum plant". True blue tourmaline is arguably the rarest color variety in the tourmaline family. Indicolite was sometimes called "indigolite", which is probably just a variant spelling. Blue tourmaline is one of the most sought after colors for tourmaline jewelry, especially since it sets and wears so well. Indicolite is found in a wide range of color hues, from blue-green to neon blue. One of the best known varieties of indicolite is Paraiba tourmaline, which is available in gemstones in a rich neon blue color (usually the result of color treatment).

  • Created By : 12-May-2016
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lapis
6.1" 4.0 pound gem grade polished lapis lazuli

Lapis Lazuli is a semi-precious gemstone, prized for over 6,000 years for its intense blue color. The name lapis lazuli means blue stone. It is a popular semi-precious gemstone today, and is arguably one of the world's most important opaque gemstones.

  • Created By : 14-Dec-2014
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  • Published In: Mineral Species
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How a Long-Misplaced Lot of Gem Liddicoatite Tourmaline Crystals
from Madagascar Came to Be Re-Discovered after 50 Years


Figure 1. Polished slice of liddicoatite tourmaline from crystal 3: 0.5 x 19.5 x 17 cm, 685 grams, Anjanabonoina Mine, Madagascar.

It was a classic New England October afternoon, with the maple leaves outside the window turning orange and red in the bright sunshine, when I received the email from David Westhoff. He wrote that he had some large, gem tourmaline crystals, and wondered if I might be interested. Was I interested? Of course I was!

  • Created By : 14-Dec-2014
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8.8" Lightning-struck Quartz, Diamantina, Minas Gerais, Brazil

For many years, itinerant miners in of the Serra de Espinhaco Mountains of Brazil have reported finding "flash stones" - now demonstrated to be the result of lightning traveling through a quartz crystal while still in the ground. The Espinha?o range is frequently hit by orographic thunderstorms, which produce the greatest number of lightning strikes. Interestingly, orographic lightning has some peculiar features: it reaches velocities of 160,000 m/s (524,934 ft/s), and it achieves plasma temperatures of 30,000°C in nanoseconds. Evidences of the effect of this special lightning on lightning-struck quartz crystals are the presence of beta-quartz (which only forms at temperatures over 573°C), along with the presence of cristobalite, the high-temperature modification of quartz (which forms at temperatures of about 1,715°C). Also, an enormous pressure of about 35.00 bar (508 psi) is evidence by the presence of coesite, the rare high-pressure polymorph of quartz. The stresses caused by this very rapid heating and cooling, along with the intense electrical charge and the high pressure, creates a characteristic zig-zag fracture pattern on the surface of the affected quartz crystals.

  • Created By : 14-Dec-2014
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Arguably the finest green mineral on the earth, malachite's rich, vivid, vibrant green color makes it unique in the mineral kingdom. Because it is available in a diverse variety of forms, it's a great choice for creating a suite of specimens in a larger collection. And, since it is not rare, good examples are affordable enough to make it a good choice for even those collectors on the tightest of budgets.

  • Created By : 16-Dec-2014
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2" 57 carat Moldavite - Czech Republic

Moldavite is a glassy variety of tektite of cosmic origin that is a bottle-green to olive-green. It is now widely believed to have been formed by the impact of a meteorite, and is only found in the Czech Republic, primarily in southern Bohemia. It is one of a handful of gems that can claim an extraterrestrial origin. It is a popular stone with both meteorite and mineral collectors, and is also used in jewelry. It is rarely seen as gemstones, but is very popular as wire-wrapped pendants.