Green Diamonds

The green color in natural diamonds primarily results from exposure to natural radiation during their geological residence near radioactive minerals containing uranium or thorium. This radiation displaces carbon atoms in the diamond’s crystal structure, creating defects that absorb red light and reflect green wavelengths. The intensity of the green color depends on radiation exposure duration and the specific structural changes that occurred. Unlike other colored diamonds, green diamonds often show color primarily on their surface rather than throughout the entire stone.

Green diamonds are exceptionally rare, accounting for less than 0.1% of all colored diamonds recovered worldwide. They rank among the rarest fancy colors alongside red and violet diamonds, making them significantly more scarce than browns, yellows, or even blues. Pure green diamonds without secondary color influences are particularly rare, with most showing modifying hues such as yellowish-green or bluish-green. This extreme rarity translates directly to their high market value and collectible status among connoisseurs of rare gemstones.

The most valuable and sought-after green diamonds display a pure, vivid green color known as “Grass Green” or “Emerald Green” without secondary color influences. Fancy Intense Green and Fancy Vivid Green command the highest prices, sometimes exceeding $500,000 per carat for exceptional specimens. Bluish-green diamonds also attract premium prices due to their appealing teal appearance and extreme rarity. The value hierarchy generally follows: pure green > bluish-green > yellowish-green > brownish-green, with intensity and saturation significantly impacting worth within each category.

Determining if a green diamond is natural or treated requires examination by specialized gemological laboratories using advanced spectroscopic techniques. Natural green diamonds typically show surface-confined coloration called a “skin” or “radiation stain,” while the color in treated stones often penetrates deeper. Under microscopic examination, natural greens may show characteristic radiation stains appearing as spots or patches. Always purchase green diamonds with certificates from respected laboratories like GIA that specifically verify natural origin, as treated green diamonds have significantly lower value than their rare natural counterparts.