Natural Blue Star Sapphire
Natural Blue Star Sapphire (Burma)
COLOR: It has a nice Blue Colour.
CHEMICAL COMPOSITION: Al2O3 Corundum (Aluminium Oxide)
CUT: Oval Cabochan. Top Quality
SPECIFIC GRAVITY: 3.95-4.03
REFRACTIVE INDEX: 1.762-1.788
HARDNESS: 9(Hardest after Diamond)
FORMATION: A star sapphire is so named due to the appearance of a star-shaped format which presents itself when the sapphire is lit by a single top-down light source. This format is the result of a phenomenon well-known as an asterism can be found in several types of gemstone, in star sapphires they are due to intersecting needle-like impurities. The inclusion is often the mineral rutile, a mineral composed primarily of titanium dioxide.
TREATMENT: One of the most common treatments performed on star sapphires is the diffusion process. In the general treatment applicable to faceted stones, a coloring element also called chromophore is applied to the surface of a natural colorless sapphire and the stone is heated to high temperatures for 7-8 days. This results in the diffusion of the chromophore in the surface of the gemstone thereby making the colorless sapphire have a blue surface layer. The overall appearance of such a sapphire becomes blue however the colored layer is very thin. In case of Black star sapphires as well as Blue Star Sapphires, such a treatment is very common.
UNUSUAL PROPERTIES: Similar to the Blue Sapphire, differs in that it has an aqueous inclusion in its makeup that creates a refracted five-pointed star on the stone’s surface. This star is a focus point in the gem. Recommended for people who wish to awaken or heighten their psychic abilities. Star sapphires usually have six ray stars, but twelve ray stars are also known. Rarely, when sapphires are cut in cabochon, they can demonstrate a cat’s eye effect. This effect displays a thin band of light down the centre of the stone and is known as chatoyancy. Works as a relaxing agent during times of extreme physical exertion. Healers of the spirit and body are often drawn to this stone.
BIRTHSTONES: A star sapphire is given on the 65th wedding anniversary. It is also one of the birth stones for the Zodiac signs of Pisces, Taurus, Virgo and Sagittarius.
USAGE: Rings, Bracelet, Pendants or lockets, necklaces or any other jewellery.
WHAT WE SUPPLY: Best quality Blue Star Sapphire in Oval Cabochan Cut with below sizes.