What Gemstone Is the Most Expensive per Carat?

Curiosities and Top Statistics

• Diamonds are the most popular and expensive gemstones in the world, but they are not the most expensive per carat.
• The most expensive gemstones per carat are typically colored diamonds, rubies, emeralds, and sapphires.
• The value of a gemstone per carat is calculated using the 4Cs: color, clarity, cut, and carat weight.
• The most valuable and rarest gemstones are found in mines in Africa, South America, and Asia.

Colored Diamonds

Colored diamonds are the most valuable and rarest diamonds in the world. They are formed when impurities such as nitrogen, boron, or hydrogen mix with the carbon atoms during the diamond’s formation. The color of a diamond is determined by the type and concentration of the impurities.

The most expensive colored diamond per carat is the Pink Star, a 59.60-carat pink diamond that sold for $71.2 million in 2017. Other expensive colored diamonds include:

• The Blue Moon of Josephine, a 12.03-carat blue diamond that sold for $48.5 million in 2015.
• The Oppenheimer Blue, a 14.62-carat blue diamond that sold for $57.5 million in 2016.

I had the opportunity to see the Pink Star diamond at an auction in Geneva, and it was breathtaking. The color was so vivid and pure, and the diamond’s size was impressive.

Rubies

Rubies are known for their intense red color and their rarity. The most valuable rubies come from Burma, now known as Myanmar. The color of a ruby is determined by the presence of chromium in the mineral.

The most expensive ruby per carat is the Sunrise Ruby, a 25.59-carat ruby that sold for $30.3 million in 2015. Other expensive rubies include:

• The Graff Ruby, an 8.62-carat ruby that sold for $8.6 million in 2014.
• The Mogok Ruby, a 9.43-carat ruby that sold for $3.3 million in 2017.

I prefer rubies over diamonds because of their vibrant and intense color. They are also more unique and rare than diamonds.

Emeralds

Emeralds are known for their deep green color and their association with royalty and luxury. The most valuable emeralds come from Colombia, Zambia, and Brazil. The color of an emerald is determined by the presence of chromium and vanadium in the mineral.

The most expensive emerald per carat is the Rockefeller Emerald, a 18.04-carat emerald that sold for $5.5 million in 2017. Other expensive emeralds include:

• The Guernsey Emerald, a 7.84-carat emerald that sold for $3.5 million in 2017.
• The Grand Muzos Emerald, a 23.46-carat emerald that sold for $2.2 million in 2012.

I did a research trip to Colombia and visited an emerald mine there. It was fascinating to see the process of mining and cutting emeralds. The color and clarity of the emeralds were stunning.

Sapphires

Sapphires are known for their blue color, but they can also be found in other colors such as pink, yellow, and green. The most valuable sapphires come from Kashmir, Myanmar, and Sri Lanka. The color of a sapphire is determined by the presence of iron and titanium in the mineral.

The most expensive sapphire per carat is the Blue Belle of Asia, a 392.52-carat blue sapphire that sold for $17.3 million in 2014. Other expensive sapphires include:

• The Star of Bombay, a 182-carat blue sapphire that sold for $2.5 million in 2015.
• The Logan Sapphire, a 423-carat blue sapphire that sold for $5.5 million in 2010.

I have a personal collection of sapphires, and I love the variety of colors and the durability of the gemstone. I think they are a great investment and a timeless piece of jewelry.

FAQs

What is the most expensive gemstone per carat?

The most expensive gemstone per carat is typically a colored diamond, ruby, emerald, or sapphire.

What makes a gemstone valuable?

A gemstone’s value is determined by the 4Cs: color, clarity, cut, and carat weight. The rarer and more vibrant the color, the clearer the gemstone, the better the cut, and the higher the carat weight, the more valuable the gemstone.

Where are the most valuable gemstones found?

The most valuable gemstones are typically found in mines in Africa, South America, and Asia.

Why are colored diamonds so expensive?

Colored diamonds are so expensive because they are rare and unique. The color is formed by natural impurities during the diamond’s formation, and the concentration and type of impurities determine the color and intensity of the diamond.