Ruby Zoizite
Ruby-zoisite is the natural combination of both ruby and zoisite crystals in a single specimen. It is also known as 'anyolite', a name derived from the Masai word for 'green' (anyoli). Other name variations include "ruby-in-zoisite" and "Tanganyika artstone". Ruby-zoisite was discovered at the Longido mining district in northeast Tanzania by Tom Blevins, an English prospector. To this day, Tanzania remains the only source for ruby-zoisite. Blevins had initially thought that he had found vast ruby deposits in 1949, but it later turned out to be a green zoisite matrix with large inclusions of mostly opaque ruby. Ruby-zoisite is also heavily included with black hornblende minerals.
Depending on its primary constituents, ruby-in-zoisite can vary tremendously in color, pattern and hardness. Zoisite provides an earthy green color, while ruby inclusions give it pink and red highlights. Zoisite's hardness ranges from 6.5 to 7 on the Mohs scale, whereas ruby has a hardness of 9. Although ruby-zoisite is not fine ruby, it eventually found a purpose in carvings and cabochons. Today, it is one of the most colorful ornamental gemstones available, and the abundance of gemstone material makes it very affordable even in larger sizes.