Ruby zoisite is a metamorphic rock made up of chromium-zoisite (bright green), pargasite (dark green almost black) and porphyroblasts, often very large, of bright red corundum (ruby). Another very common term to identify these rocks is anyolite. Ruby zoisites were discovered in 1954 by Tom Blevins (a British mining researcher) in northeastern Tanzania. Since then, Tanzania remains the only place in the world where there is news of the presence of such rocks. The rubies present within these rocks are not suitable for commercial use as their quality is not such as to be able to define them as gems, in fact the crystals very often have fractures and opacity.
Dimensions
Height (mm): 25
Thickness (mm): 8
Width (mm): 18
Weight (g): 6.9
Property
Chemical formula: -
Mohs scale: 6-7
Relative Density: 3.15-3.36
Crystal System: Orthorhombic