Heat Treated Sapphire Inclusions

Many sapphires have inclusions of very fine hair like crystals of a mineral called rutile.

Heat treated sapphire inclusions.

So why are some sapphires heat treated. A case in point is the internal diffusion seen in a heat treated sapphire induced as the titanium from rutile silk inclusions was dissolved into the crystal lattice of the host sapphire at high temperatures. The particles give the stone a sleepy or hazy appearance which is common to sapphires from kanchanaburi thailand. Inclusions in natural synthetic and treated sapphire.

Sapphire treatment guide heated. The application of heat treatment on sapphires dates back. Here it is true that not every stone can be changed to optimum colours by temperature treatment i e. Heating sapphires at extreme temperatures change the internal characteristics so much that it is quite easy for a trained gemologist to determine if the sapphire has been heated.

In this treatment rubies and sapphires are usually heated above 1200 c. Shigley aug 7 2017. Mcclure kevin schumacher and james e. Other images highlight features that may be diagnostic for a particular treatment.

Photo courtesy of apsara co uk. Distinguishing these levels of treatment can also affect the price of a sapphire dramatically. Rutile is a titanium oxide and often it forms in conjunction with a sapphire crystal becoming embedded within the structure of the crystal. The study of inclusions in sapphires is a sure way to detect if a sapphire has been treated.

The raw material for this is also limited. There are different types and level of heat treatment in sapphires that can be classified from very slight to quite extreme. Heat treatment of sapphire a layman s simplified explanation of the various levels of treatment sapphire is formed deep down below the earth s surface some 65 kilometres down and comes to the surface in a volcanic explosion in a formation tube or vent. Why heat a sapphire.

The sapphire may be left with inclusions such as the silk veils which often. Almost all sapphires 95 of them today are heat treated. If you have been shopping for sapphires you will come across stones that are either natural no heat or enhanced by heat heated there are other methods of treatment conducted on sapphires however this article only compares unheated sapphires with heated sapphires as it is the most prevalent method of treatment in the market today. The study of inclusions in sapphires is a sure way to detect if a sapphire has been treated.

Heating sapphires at extreme temperatures change the internal characteristics so much that it is quite easy for a trained gemologist to determine if the sapphire has been heated. This changes the value of certain colour effective trace elements which explain the colour optimisations. The photo above visually shows why.