Ruby is one of the most expensive precious stones. Its name comes from the Latin „rubeus’, meaning ’red’. Its colour is caused by a small amount of chrome. Ruby belongs to Corundum, just like the blue Sapphire. Besides these colours Corundum can be green, yellow, brown, violet-scented and yellowish-reddish. Corundum is the second hardest material on Earth after Diamond. Colours are usually not homogeneous, there might be lighter and darker marks and layers in the stone, sometimes such stones are found with each ends in different colours.

Among Rubies the most popular and respected ones are carmine red coloured.

The most important localities are Burma and Ceylon.

Ruby is usually cut to brilliant shape, but the staged or mixed cuts are also popular. 

 Mohs: 9.