Spinel is a hard vitreous magnesium aluminum oxide, and comes in a range of other colors, but those varieties are transparent. Black Spinel not only has the dark color, but...
Blue Apatite ranges in color from light teal to blue to bright blue to dark blue to green. It can be easily confused with other minerals due to its variety...
Chrysoprase is a bright apple green, translucent stone, whose color often caused ancient jewelers to confuse it with Emerald. A cryptocrystalline Chalcedony, its brilliant color comes from the presence of...