S A P P H I R E

 

Hardness 9
Modern birthstone: September

 

Any stone referred to as a sapphire is blue, all the other colours are qualified by description i.e. yellow sapphire, green sapphire, pink sapphire, violet sapphire, and red sapphires. The colouring pigment in blue sapphire is iron and titanium;  in violet stones, vanadium.  A small iron content results in yellow and green tones, whereas chrome produces pink. The most highly sort after colour is “cornflower blue” which used to be called “Ceylon sapphire”.  Like Burma-rubies, this refers to the specific colour as opposed to where they are mined. Sapphires are more common than rubies, and as with rubies you can get “cat’s eye” sapphires. Most common deposits are found in Burma, Sri Lanka, Thailand and India. Large stones are rare, and synthetic sapphires  have also been on the market since the beginning of 1900. The same methods are used in recognising a synthetic from a natural, by  the inclusions and colour banding which are very specific to corundum.