The most commonly known gemstone is diamond. Diamond and its variants are also the most expensive gemstones. But there are several other expensive gemstones that might not be as pricey as diamond but are beautiful, rare and valuable with their own remarkable history.
The most expensive gemstone known to mankind is a blue diamond costing nearly $4 million per carat.
Gemstones are one of the most iconic parts of human’s history and culture, weather as amulets and charms or adornments to the nobles. Some of the major factors that determine the value of a gemstone are its size, crystal structure, optical properties, rarity and hardness.
We have included some of the most valuable and expensive gemstones on our list below according to their prices per carat in today’s context.
Spinel ($5,000 per carat)
Spinel has been one of the favourites among collectors. You are unlikely to find one as the supply of natural spinel is very limited. Spinels are one of the hardest gemstones and are suitable for all kind of jewelry.
A spinel named the ‘Hope Spinel’ weighing 50.13-carats was sold in 2015 for $1.47 million setting a world record of the most expensive spinel ever sold.
Sapphire ($8,000 per carat)
Sapphire are mostly mined in Sri-Lanka but can also be found in Madagascar and Tanzania. Padparadscha sapphire is the world’s rarest and expensive sapphire which has a pinkish-orange color.
However, a blue 392.52 cushion-cut sapphire named the ‘Blue Belle of Asia’ was sold at auction in Geneva for $17.3 million 2014 making it the most expensive sapphire ever sold.
Black Opal ($9,000 per carat)
Black opal is the most valuable and desired among opals and features a dark body ranging from dark grey to jet black. Opals are extremely sensitive to shocks and temperature changes. They are mostly mined in Lightning Ridge in northern New South Wales and have also been found in South Australia.
A black opal by the name, ‘Royal One’ weighing 306-carats is the most precious in the world which is valued at $3 million.
Red Beryl ($10,000 per carat)
First discovered in 1904, most of the fine specimens of red beryl are guarded and never faceted by mineral collectors due to its rarity. They exhibit a few different shades of a darker red color.
Despite of not being emeralds, red beryl often features inclusions and fractures similar to emeralds. Prices of these gemstones can vary, but to find one for purchase is extremely difficult.
Emerald ($12,000 per carat)
Emeralds are some of the most popular gemstones found primarily in Brazil, Colombia, Zimbabwe and Zambia. Most natural emeralds available on market include minor imperfections and finding the perfect one is quite rare.
The world’s most expensive emeralds by the name, ‘Rockefeller Emerald’ weighs 18.04-carats and was sold at the Christie’s auction for $5.5 million.
Ruby ($15,000 per carat)
Commonly referred to as the ‘King of Gemstones,’ rubies feature spectrum of vibrant red hues. Rubies are one of the most durable gemstones and are subjected to more treatments than any other gems.
In 2015, an extremely rare Burmese ruby named the ‘Sunrise Ruby’ was auctioned at a Sotheby’s event. Sunrise Ruby weighed 25.59-carats and was sold for over $30 million making it the most expensive ruby ever sold.
Jadeite ($20,000 per carat)
Jadeite is the rarest and purest gemstone in the Jade family. It is available in a variety of colors such as red, yellow, black and green.
A specific shade of semi-transparent emerald green known as ‘Imperial Jade’ is the most sought jadeite in the world. The ‘Hutton-Midivani Necklace’ which consists of 27 top quality jadeite beads was sold at auction for $27.44 million setting a record for the most expensive jadeite jewelry ever sold.
Musgravite ($35,000 per carat)
Musgravite was first discovered at the Musgrave Range in Australia in 1967. But the first sizable gem-quality musgravite specimen was found in 1993 which was large and pure enough to be cut and shaped.
As of 2005, only 8 known specimens of musgravite are known to exist and it is difficult to put a price tag on this gemstone due to its exceptional rarity. It is often mistaken because of its similarity with taaffeite.
Alexandrite ($70,000 per carat)
Alexandrite was discovered in Russia during 1830s. Alexandrite is a very rare and also hard to aquire gemstone popular for its optical properties and can undergo dramatic color shifts depending on the lighting condition. It changes color as you rotate it.
The Smithsonian Institute owns what is believed to be the largest faceted alexandrite in the world which is a cushion-cut stone weighing 65.08-carats valued at over $4 million.
Blue Diamond ($100,000 per carat)
Diamonds are the hardest substance found on earth and arguably the most popular gemstones. Colored diamonds are the most expensive gemstones ever with a wide spectrum of color including blue, black, brown, pink, cognac, champagne, green, red and yellow.
Blue diamond is the rarest and most valuable among diamonds after its pink variants. The ‘Oppenheimer Blue’ diamond is the largest vivid blue diamond known. It weighs 14.62-carats and was sold for $57.5 million at Christie’s Magnificent Jewels auction.