Those who have been tasked with providing non-scientific names to the innumerable gemstones discovered over the millennia have not had an easy job. Thousands of different minerals have required distinctive names, yet the gemstones are often so similar and the adjectives seem limited when describing a mysterious blend of chemicals and elements. It's no surprise then that many gemstones have been tagged because their patterns and highlights are similar to others found elsewhere in nature.
What else would you call a stone whose interior alternates dark bands with bright orange or yellow bands? Tiger Iron invites the comparison from anyone who has seen the colorful, parallel stripes of a tiger.
Those colors and natural luster make it a popular gemstone among jewelry makers as well. It's much the same with Iron Zebra Jasper, where black stripes evoke another member of the wild kingdom.
Chatoyancy is responsible for some of Tiger Iron's reflectancy, and is defined as "[arising] either from the fibrous structure of a material, or from fibrous inclusions or cavities within the stone." It's why Cat's Eye is so named, and why many gemstones are cut the way they are, in an effort to bring out the chatoyancy. Wearing a piece of jewelry with a cat's eye effect gets noticed, since it's human nature to make eye contact, even when it comes from a stone in a necklace.
Tiger Iron is actually composed in part of Tiger Eye, a yellowish-brown quartz with a chatoyant layer, along with Red Jasper and Black Hematite. It is also sometimes called Mugglestone. but that's clearly an inferior name. It's been mined in such disparate places as Australia, Brazil, England, Mexico and near Lake Superior.
Other stones we are featuring this week have names derived from animals. Maybe without seeing them, you can picture what Crocodile Jasper (aka, Kambaba) looks like!
- Jeff S.