What Is A Precio us Stone? a highly attractive and valuable peice ofmineral used in jewellery. Also called a gem. Emerald a bright green precious stone Ruby a deep crimson (red/purple) to pale rose coloured precious stone. Garnet a deep red coloured precious stone Pearl not a stone (mineral), but a hard shiny material formed in an oyster shell, used as a precious stone (gem) Amethys t a violet or purple precious stone Diamond : a precious stone consisting ofa clear crystalline form of pure carbon Sapphir e a blue coloured precious stone Opal precious stone Topaz precious stone jade
