When you think of expensive gemstones, what comes to mind? Most people think of the Big Four: diamonds, emeralds, rubies and sapphires. However, it might surprise you to know that there are ...
We have all seen the sparkling gemstone amethyst at shops that specialize in rocks and minerals (“crystals”) often prominently displayed on the main counter just waiting to catch an eager eye.
People view the 12-foot tall amethyst geode from Uruguay hosted at the American Museum of Natural ... [+] History in New York. Thanks to geological surveys and detailed chemical analysis ...