Emerald

Emeralds are medium to dark green beryl which derives its color from chromium and vanadium. Emerald has a hardness rating of 7.5. The best known sources include Colombia, Zambia. Almost all emeralds contain numerous small inclusions and fractures that promote fragility. Most stones on the market are impregnated with oils, waxes, or other substances to mask the fractures and sometimes enhance color.