Star Sapphire

A cabochon cut star sapphire characteristically shows a six-rayed star, caused by needle-like "silk" inclusions that reflect and scatter light.
Star sapphires range from semitransparent to opaque.

They come in the same colors are regular sapphires do with some being very limited such as:
Green, yellow and orange star sapphires which are very rare.

Black, dark brown, dark blue and general dark colors are common and are not very expensive up to certain sizes and star qualities.
Please note, that more rays is not a better star, 6 rays (3 intersecting lines) are the most desirable stars.

Many of the star sapphires out there are regularly heated and oiled during production in order to improve the color and star effect.

Heating and oiling rubies and sapphires are a common practice today and are accepted in the industry.

One should watch out for synthetics which are not plastic, but lab grown star sapphires created by flame fusion. Also as a rule of thumb, "Linde" Star Sapphires/Rubies are not worth anything but are very nice for decoration and have a beautiful star which is basically man-made.

Regardless, most stars under 10 carats are not super expensive, however if you are looking for a fine stone do your research and look for a reputable certificate.

Thanks,

Kevin
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