Rough diamond / Ring / new- 1.68 g - (1)

Rough Diamond Ring / new Set in 925 sterling silver Total weight: 8.4 ct / 1.68 g 7.4 mm x 5.3 mm New and unworn Ring size: EU 59 UK R US 8.7 FR 19 Inner diameter: 18.8 mm Diamond is the cubic modification of carbon and, as a naturally occurring solid, a mineral from the class of elements. Diamonds typically form octahedral crystals, often with curved and striped faces. Other observed shapes include tetrahedron, dodecahedron, and cube. The crystals are transparent, colorless, or colored green, yellow, brown, and less commonly orange, blue, pink, red, or gray to black due to impurities (e.g., nitrogen or boron) or lattice defects. Diamond is the hardest natural substance. On the Mohs scale, it has a hardness of 10. Its abrasive hardness (Rosiwal hardness) is 140 times greater than that of corundum. However, the hardness of the diamond is anisotropic—depends on crystal direction. This makes it possible to cut diamond with diamond. In the diamond powder used for cutting, the crystals occur in every orientation (statistical isotropy), so the hardest among them always act on the surface to be ground. Diamond is optically isotropic with high refractive index and high dispersion. It exhibits fluorescence and phosphorescence and is tribolectric. It has the highest thermal conductivity of all known minerals. Shipping as insured registered mail

Estimation:€4

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