The Allure of Gemstones

A 59.6-carat pink diamond, known as the “Pink Star” sold at auction for $71.2 million in 2017. While the “Pink Star” holds the record for the highest priced gemstone ever sold, it is not the highest price per carat the world has ever seen.

That honor goes to the 14.6-carat “Oppenheimer Blue” diamond that sold for $58 million, or nearly $4 million per carat, in 2016.  

While you likely don’t have a 59-carat gemstone on display in your living room or collecting dust in your closet, chances are, you do have a few gemstones floating around that could be valuable.  

For instance, we sold a 1.5-carat diamond pendant necklace for $5,500 in July and a beautiful diamond and alexandrite ring for $650 earlier this month.  

What is a gemstone?

A gemstone is a precious or semiprecious stone. Common gemstones you’ve likely heard of include diamonds, sapphires, emeralds, rubies and opals.

They are typically cut, polished and used in a piece of jewelry. But, they don’t have to be. Some gemstones are loose and have not been set in jewelry. Others are considered rough gemstones, meaning they have not been cut or polished.

What makes a gemstone valuable?

Chances are a gemstone is valuable to you because of the memories attached to it. A beautiful ring you inherited from your grandmother, a gift from your parents when you graduated college, the engagement and wedding ring set you would never willingly remove. All these gemstones have sentimental value that is difficult to quantify.

But if you’re planning to buy or sell a gemstone, it’s important to keep the following in mind when determining a stone’s value:

  • Carats – This describes the size of the gemstone. Size matters when it comes to gemstones and if everything else is equal, a larger stone is worth more.
  • Color – Are you purchasing a colorless diamond or a colored gemstone? The optimal color for each different gem is different. In general, brighter colors are worth more than pale colors, with the exceptions of tourmaline and colorless diamonds.
  • Cut – The shape a stone is cut into and the quality of the cut adds value to the gem. Rough gemstones are typically much less valuable than ones that have been expertly polished and cut.
  • Clarity – Some colored gemstones almost always have inclusions, while some typically look clean to the naked eye. With a few exceptions, the more clarity a stone has the more valuable it will be. Clarity is especially important in colorless diamonds.  
  • Location – In some cases, the location where a gemstone was mined can impact the value of the stone by more than 15%.

Do you have questions about a gemstone collection or some pieces of fine jewelry you think could be valuable? Consult with a certified appraiser or take advantage of a free appraisal fair to get a better idea of the value of your collection.  


Erik Hoyer owns EJ’s Auction & Appraisal in Glendale. 

Contact him at, or 623-878-2003.


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