Corundum is the family name for rubies and sapphires.  All coloured stones except the red coloured stones of this gemstone family are generally known as sapphires, while the red coloured stones in this gemstone family are only known as rubies.

 

Corundum is a relatively hard gemstone with a rating of 9 on the Mohs scale, corundum is also one of the

most treated and also currently the most synthetically created of all the gemstone families. 

To the untrained eye a ruby is a ruby and a sapphire is a sapphire, but this is not necessarily true. 

 

Both natural and created corundum are chemical replicas of each other, however, it’s the method of creation that reveals and distinguishes them apart.   This is also not a new occurrence with the first created ruby made in 1837 and the first commercially released around 1885 and the first created sapphire released around 1910.  So even your grandmothers’ precious ruby ring may fall into the created category.   

 

If you know or do not know that your ruby or sapphire is natural or created it can be cleaned ultrasonically or with steam.  However if it is know that your ruby or sapphire has been treated either with heat or by lattice diffusion it may still be cleaned this way. 

 

If it is unknown regarding treatment the ruby or sapphire should not be cleaned using ultrasound or steam as damage will inevitably result.  A fracture-filled, cavity filled or dyed and or oiled gemstone (natural or created) should only be cleaned with a damp cloth.  No acids or harsh chemicals should ever be used, even lemon juice can cause damage to this type of treated stone.

 

Ire on the side of caution, and if in doubt ask a professional gemmologist!