Green Tourmaline is found in many countries but from a commercial aspect Brazil, Mozambique, Nigeria, the Congo, Malawi, Afghanistan and Madagascar are main sources. However Maine and Californian Tourmaline from the US as well as Russian tourmaline from the Urals is also popular when available. Greens in the medium colour range are usually most desirable since if the material is darker or olive toned it becomes less than lively when cut. Since tourmaline is a dichroic gem (can show different colours when viewed from different angles), it is important to orient the rough so that the better colour shows predominantly when viewed through the crown and table. |