Top Most Expensive Stones by Price per Carat
The Pink Star diamond, a 59.60 carat internally flawless vivid pink stone, sold at Sotheby's Hong Kong in 2017 for $71.2 million, setting a world record for any gemstone at auction. This price translates to roughly $1.19 million per carat, making it the most expensive diamond ever sold. The Blue Moon of Josephine, a 12.03 carat vivid blue diamond, sold in 2015 for $48.5 million, or approximately $4.03 million per carat, establishing a benchmark for blue diamonds. Both stones are certified by the Gemological Institute of America and are documented in auction records from major houses like Sotheby's and Christie's as reported by Forbes.
Beyond diamonds, the Jadeite necklace "Hutton-Mdivani" sold at Sotheby's Hong Kong in 2014 for $27.44 million, making it the most expensive Jadeite jewelry ever auctioned. The necklace contains 27 beads of the finest Imperial Jade, with a record price of over $3 million per carat for the largest bead. Red Beryl, a rare variety of beryl found primarily in Utah and New Mexico, commands prices of $10,000 to $20,000 per carat for gem-quality stones, far exceeding the per-carat value of many diamonds. Alexandrite, known for its color-change property, can reach $70,000 per carat for top specimens from Russia's Ural Mountains.
Rarest Gemstones and Their Market Value Drivers
Red diamonds are the rarest colored diamonds, with only a few dozen known gem-quality stones. The Moussaieff Red, a 5.11 carat fancy red diamond, is valued at an estimated $20 million, or roughly $3.9 million per carat. Painite, once considered the rarest mineral on Earth, was listed in the Guinness World Records as the rarest gemstone mineral, with only a few thousand crystals known. Faceted painite gemstones sell for $50,000 to $60,000 per carat, driven by extreme scarcity and demand from collectors per the Gemological Institute of America.
Serendibite, a calcium magnesium aluminum sorosilicate, is one of the rarest gemstones, with only a handful of faceted stones over 1 carat known to exist. High-quality specimens have sold for over $1.8 million per carat at auction. Taaffeite, discovered in 1945, is another ultra-rare gem that can command $35,000 per carat for clean, vivid stones. These prices are driven by the intersection of extreme rarity, high clarity, and strong collector demand, with auction houses like Christie's and Sotheby's serving as primary price discovery venues as detailed by Christie's.
Companies, Certifications, and Investment Trends
Major auction houses such as Sotheby's and Christie's dominate the high-end colored stone market, with their annual Magnificent Jewels sales setting benchmark prices for rare gems. The Gemological Institute of America and the International Gemological Institute provide the primary certification standards for the most expensive stones,