A mineral name; a green variety of garnet. Used in geology and gemology.
Grossular is a type of garnet that contains calcium.
柘榴石 is the general term for garnet, while 緑柘榴石 specifically refers to the green grossular variety.
Compound of 緑 (みどり, 'green') + 柘榴石 (ざくろいし, 'garnet'). The exact historical derivation is uncertain, but the name describes the mineral's typical green color.