Zircon is the birthstone for December. It bursts with brilliance and fire and is available in yellow to golden, champagne, brown and rich burnt reds. The yellow / brown tones are heated to produce blue and white coloured Zircons. It is a great alternative to coloured diamond and has a hardness of 7.5. Zircon is mined in Sri Lanka, Cambodia, Burma, Tanzania, Madagascar, Mozambique and Australia. The RI is above 1.81 (except green low type) and the specific gravity of Zircon is 4.60-4.80.