Certified Konerupine Brownish Yellow 5.97 Cts Loose Gemstone 12911
KONERUPINE BROWNISH YELLOW 5.97 CTS 12911 RARE COLLECTORS GEM. 13.1 x 9.5 mm. 100% Natural - Not treated in any way.
Suitable for Museums, Institutions and Students of Gemology. Will make a Gorgeous Ring or Pendent accented with Diamonds. Gem with High Luster and Good Clarity.
A Gem of Lasting Beauty. Refractive Index: 1.665 1.683 Hardness: 6.50 Chemical Comp : Mg4(Al, Fe)6(Si, Al, B)5O21(OH), Density: 3.25 - 3.35 Crystal Group: Orthorhombic. Kornerupine is a rare gem, Sri lanka is the main source country. This gem is pleochroic and comes in Green brown and yellow green. Kornerupine is a rare boro-silicate mineral with the formula (Mg, Fe2+)4(Al, Fe3+)6(SiO4, BO4)5(O, OH)2. It crystallizes in the orthorhombic - dipyramidal crystal system as brown, green, yellow to colorless slender tourmaline like prisms or in massive fibrous forms. It has a Mohs hardness of 7 and a specific gravity of 3.3 to 3.34. Its indices of refraction are na=1.660 - 1.671, nß=1.673 - 1.683 and n? =1.674 - 1.684. It occurs in boron-rich volcanic and sedimentary rocks which have undergone high grade metamorphism. It is also found in metamorphosed anorthosite complexes. Kornerupine is valued as a gemstone when it is found in translucent green to yellow shades. The emerald green varieties are especially sought after. The item "CERTIFIED KONERUPINE BROWNISH YELLOW 5.97 CTS LOOSE GEMSTONE 12911" is in sale since Saturday, August 25, 2018. This item is in the category "Jewelry & Watches\Loose Diamonds & Gemstones\Loose Gemstones\Kornerupine".
- Shape: Oval
- Country of Origin: Sri Lanka
- Country/Region of Manufacture: Sri Lanka
- Natural/Lab-Created: Natural
- Length: 13.1 mm
- Width: 9.5 mm
- Certificate: CGJ
- Cut Grade: Good
- Transparency: Transparent
- Treatment: None (No Enhancement)
- Brand: Cresla
- Total Carat Weight (TCW): 5.97