Black Star Sapphire Rough

Among all black star sapphire the most precious one is thai star sapphire.

Black star sapphire rough.

Black sapphire vs black star sapphire. Star sapphire is a type of sapphire displaying an optical star like effect. 1280 cts 100 natural untreated unheated black star sapphire rough gemstone gemsbazarindia. Star sapphires contain intersecting needle like inclusions that cause the appearance of a six rayed star shaped pattern.

Black star sapphires owe their stars and their dark color to included crystals of the shiny mineral hematite. The inclusions are typically the mineral rutile but in black star sapphire it is inclusions of hematite that cause the star effect. Star sapphire is a type of sapphire that exhibits a star like phenomenon known as asterism. Black sapphire pear 5 63 ct.

This is one of the largest pieces of rough black star sapphire i have ever seen. This effect is caused by asterism. A very large piece of rough black star sapphire. Tiny needles of silk within the sapphire crystal reflect light and form a star sapphire s telltale star.

The most common star pattern is a 6 rayed star although star sapphires with 4 rays and 12 rays have been found. This gemstone has level of hardness 9 on the mohs scale which is similar or near to diamond thus this can be said it is the hardest substance next to diamond. Although black sapphire is not a very popular or sought after gemstone this is not the case for black star sapphires. As mentioned above it is rare that an exceptional rough star sapphire crystal isn t subjected to heat treatment to turn it into a more valuable transparent stone.

It can take a lot longer to cut and shape a piece of this size into a cabochon because there is so much material to remove. This however is not true. Make offer 1240 cts 100 natural untreated unheated black star sapphire rough gemstone 32500 cts 6 500 kg 100 natural golden star sapphire rough loose gemstone 1 499 99. Many people think that black star sapphires are an entirely different gemstone.

Though this gemstone is black under the flashlight it will give the golden colour star effect on the surface. Clarity in star sapphires is a complicated issue. Make offer 12x10 12mm x 10mm flat low dome oval black star sapphire cabochon cab gem es232 black star sapphire sri lanka natural genuine unheated gemstone gpg 677 2 100 00. Black star sapphires are black sapphires that display asterism.

You can read more about asterism in our phenomenal gems article. Black sapphire pear 5 63 ct.