A ruby is from the same family as sapphire- namely Corundum, the same basic make up being aluminium and oxygen. Chromium is also present which gives ruby its red colour, varying amounts giving the differing hues of colour.
Its the birthstone for July, and is also mostly known for being the stone associated with a ruby wedding anniversary, i.e., 40 years of marriage, but also recently associated with 15 years too. So forget the first, and you have 25 years to remember the second! Mythology says that the wearer is protected from illness and its the stone of love.
The brightness of this gem stone is that it has quite a high degree of refraction, or the way it bounces light back, giving it a bright vitreous lustre. Also it is pretty close to diamond in its hardness, being 9 on the Moh scale of degrees out of 10. It will therefore retain its look for many years if looked after carefully. It can scratch other softer gem stones, so a good idea not to drop into a jewellery box with other items of stone set jewellery.
Most rubies do have natural incursions, indeed very clear stones can have been treated in some way to remove flaws.
So no one should worry about fibrous or needle like inclusions, this is nature and what nature has naturally created! Even fine stones have this silky look, and some can form what is called an ‘asterism’ whereby a reflective six ray star effect appears on the stone. Usually seen in a cabochon cut stone, you lose clarity in this type of stone, but can be beautiful to see.
The best rubies do still come from Burma, but also Thailand, Vietnam and Sri Lanka. The best coloration is referred to a ‘pigeon blood’, although we dont actually compare a stone to the natural substance!
Heat treatment in this day and age is a very normal and usual way to deal with a ruby. This method does not devalue the stone, it just enhances the beauty of the stone, and this has been done for many decades. Less acceptable is a treatment called glass filling, and this can affect the durability of the stone.
Look at our web site www.vintagetom.co.uk for a large range of beautiful pre-owned and antique ruby rings, many set with diamonds.