You may not think that by saying “Pidgeon-red anthrax” you were referring to one of the most valuable coloured gemstone per carat; the ruby. In many cultures the ruby is known as the “King of Gems” and The Mogok Valley in Burma is an area made famous for its high quality rubies. The most fascinating of these rubies flouresce in natural light and possess the deep pink/purple colour whose description refers to the colour of the last few drops of blood which flow from a pidgeon after it has been sacrificed…(apparently!)
However grotesque the name for that particular shade of red, it represents well the sentiment for which rubies have long been famous. Until the 1920s, rubies were the gift of love and devotion. Red like the heart and flashing with such life that one Burmese ruby-wearing Queen was thought to have spirits in her ears, rubies are as mysterious and unwordly as love itself – and in fact the land which they made famous.
The Queen’s Dimaond Jubliee this year could equally have been named the Queen’s Star Ruby Jubilee, since the star ruby is the alternative stone to mark a 60 year (Diamond) anniversary. This rivaly for recognition mirrors a marketing duel between DeBeers and Burma Ruby Mines, Ltd. in the early 20th century. The bankruptcy of the latter in 1934 was not only a reflection of the slowing ruby trade but also the strength of the diamond marketers. It is only since then “diamonds are a girl’s best friend”.
Ruby is made from corundum, the second hardest naturally occuring material in the world; second only to diamond. Corundum was identified by the Romans as a “carbdon-like substance,” or in Latin “Anthrax,” a word with very different connotations today. In its pure form corundum is clear. The red colour comes from impurities which characterise it as ruby; all other colours are classified as sapphires. They grow under immense heat and pressure as hexagonal crystals, which are made from aluminium and oxygen. Having been exposed by nature’s weathering and transported downstream by rivers, rubies as rough fragments can be found in rivers or mined many metres down, often in old riverbeds.
Rubies are traditionally cut with diamond powder and abrasion; lasers are a quicker more sophisticated technique more often used in the west. This last process is just as important as its chemistry in obtaining the highest valued stone. Too deep a cut, and the stone’s brillance is not reflected; too shallow and it cannot sparkle brilliantly either.
When buying a ruby key considerations are its cut, colour, carat weight and clarity. The “inclusions” or imperfections within the ruby are characteristic of their origin. A close inspection can also reveal the “growth lines” which indicate its organic nature.
Several methods for creating rubies in a lab have been discovered in an effort to short-cut to the supply. The definitions between natural and synthetic rubies can often be made shady by tradesmen and some modern synthetic rubies show growth lines which can mislead even the educated eye. Sometimes similarly coloured natural stones can be confused too. The large red “Black Prince Ruby” which sits on the Queen’s Imperial State is infact a red spinel, a semi-precious stone, with which its identity was confused.
Synthetic rubies are useful in industry for their hardness but for jewellery the romance for which it is gifted surely lies with natural stones. Rubies are the birthstone for July and in lore they bring health, wealth and wisdom to those who wear them!