Diamond

Overview

Diamond is pure crystallized carbon, the hardest natural material on Earth. Its exceptional hardness (Mohs 10), combined with high refractive index and dispersion, produces the brilliance and fire that have made diamond the world's most recognized gemstone. India was the world's only source of diamonds until the 18th century, and the Golconda region produced legendary stones including the Hope Diamond and the Regent Diamond.

Physical Properties

Mohs hardness: 10. Refractive index: 2.417. Specific gravity: 3.52. Crystal system: cubic. Diamond has the highest thermal conductivity of any gemstone, which is why it feels cold to the touch and why thermal testers are the quickest screening tool for diamond identification. Dispersion (fire) is 0.044, producing the characteristic rainbow flashes.

The Four Cs

Diamond grading follows the standardized 4C system. Cut determines how well the stone reflects light (the most important factor for visual beauty). Colour is graded on a D (colourless) to Z (light yellow) scale. Clarity ranges from Flawless (no inclusions under 10x magnification) to Included (visible to the naked eye). Carat weight measures size. Each factor contributes to value, but cut quality has the greatest impact on a diamond's visual performance.

Fancy Coloured Diamonds

Diamonds naturally occur in virtually every colour. Yellow diamonds are coloured by nitrogen, blue by boron, pink and red by structural distortion, and green by radiation exposure. Fancy coloured diamonds above 1 carat with vivid saturation are among the rarest and most expensive gemstones in existence.

Vedic Significance

Diamond (Heera) represents Venus (Shukra) in Vedic astrology. It is prescribed for luxury, romance, artistic talent, and marital harmony. The stone should be colourless to near-colourless, eye-clean, natural, and set in platinum or white gold. It is worn on the ring finger or middle finger of the right hand on a Friday.