NATURAL BLUEISH WHITE SAPPHIRE
Shape : Cushion
Dimension : 7.2mm x 6mm x 3.5mm
Weight : 1.35cts
Clarity : Clean
Colour : Blueish white
Transparency : Transparent
Origin : Sri Lanka
Treatment : Unheated/ Natural
Sapphire deposits are found in Eastern Australia, Thailand, Sri Lanka, China, Vietnam, Madagascar, Greenland, East Africa, and in North America in mostly in Montana. Madagascar, Sri Lanka, and Kashmir produce large quantities of fine quality Sapphires for the world market. Sapphires are mined from alluvial deposits or from primary underground workings.
Bi-Color Sapphire from DanuGroup Collection
Also, Sapphire can be found as parti-color, bi-color or fancy color. Australia is a main parti-color Sapphire producer.
A star sapphire is a type of sapphire that exhibits a star-like phenomenon known as asterism.
Also, A rare variety of natural sapphire, known as color-change sapphire, exhibits different colors in a different light.
Sapphires can be treated by several methods to enhance and improve their clarity and color. A common method is done by heating the sapphires in furnaces to temperatures between 500 and 1,850 °C for several hours, or by heating in a nitrogen-deficient atmosphere oven for 1 week or more. Geuda is a form of the mineral corundum. Geuda is found primarily in Sri Lanka. It’s a semitransparent and milky appearance due to rutile inclusions. Geuda is used to improve its color by heat treatment. Some geuda varieties turn to a blue color after heat treatments and some turn to red after oxidizing. Also, Kowangu pushparaga turns to yellow sapphire after oxidizing.
Sapphire Crystal system is a Trigonal crystal system with a hexagonal scalenohedral crystal class. Sapphire hardness is 9 according to the Mohs hardness scale with 4.0~4.1 specific gravity.
Refractive index ω =1.768–1.772 nε =1.760–1.763 Solubility = Insoluble
Melting point = 2,030–2,050 °C
Birefringence = 0.008
Pleochroism = Strong
Luster = Vitreous
Sapphire is the birthstone for September and the gem of the 45th anniversary.