Amethyst Gemstone | Amethyst Stone - GIA
Amethyst Gemstone is the purple variety of the Quartz mineral. Amethyst’s purple color can range from a light lilac to a deep, intense royal purple, and from brownish to vivid.
Amethyst Description - GIA
This amethyst crystal is from Namibia. It shows classic quartz crystal shape: a six-sided columnar crystal with a pyramid-shaped termination at the top. Courtesy Daniel Trinchillo, Fine Minerals International. Amethyst is the purple variety of the quartz mineral species. It’s …
Amethyst - Gemological Institute of America
Amethyst is a gem with purple coloring that many people find very beautiful. It is the purple variety of the mineral quartz. It was as valuable as ruby and emerald until the 1800s when more amethyst was found in the country of Brazil.
Amethyst History and Lore - GIA
This ancient necklace dates to 2000BCE. An inscription on the center stone is a South Arabian script from the 8th century BCE. - From "Gems and Gemstones: Timeless Natural Beauty of the Mineral World" by Lance Grande and Allison Augustyn, 2009, University of Chicago Press. Because of its wine-like ...
Amethyst Quality Factors - GIA
This 17.53-carat amethyst displays a rich reddish purple color. - Lydia Dyer, Super Trillion Cut Amethyst gem courtesy of John Dyer & Co. Amethyst has been the most-prized quartz variety for centuries. Once available only to royalty, relatively plentiful supplies have made amethyst more widely available in modern times.
Amethyst Care and Cleaning Guide - GIA
Gem and mineral hardness is measured on the Mohs scale. The numbers are based on the relative ease or difficulty with which one mineral can be scratched by another. But the Mohs scale is deceptive. The steps between the minerals are not evenly spaced. For example, diamond is only one number away ...
紫水晶 | 紫水晶 - GIA
紫水晶是紫色的石英矿物类别。 紫水晶的紫色范围从淡丁香紫到浓艳的皇家紫，色度从褐到鲜艳。
February Birthstone | Amethyst Birthstone Source & Meaning - GIA
Amethyst, the February birthstone, is the purple variety of quartz. It is said to prevent drunkenness and make you quick witted in business. You once had to be rich to own this birthstone for February, but new finds have made it more affordable. Learn more about this stunning birthstone and where it can be found.
BIOLOGICAL DESCRIPTION OF AMETHYST simply with a diffused light source ~uch as a light table. In more difficult cases, placing a.single polariz- jug filter between the light source and the amethyst will iw~8lly m8ke the twinning visible. Finally, observatiw with the stone between crossed PO- lardds, pdbly even with lotankrsion, should resolve ...
Amethyst Buying Guide - GIA 4Cs
2014年2月1日 · Known for its majestic purple color, amethyst is the gemstone of choice for those born in February. Breathtaking and surprisingly affordable, it’s also the most valued variety of quartz.If you’re in the market for this February birthstone, GIA’s Amethyst Buying Guide has tips and advice on what to look for, including amethyst quality factors. ...