How the Size of a Ruby Affects its Value
In the wholesale gem trade, rubies are sold on a price per carat basis. Therefore, it would make sense that a 5 carat ruby would cost more than a 1 carat ruby, all else being equal. However, an aditional factor is that it is rarer to find a 5 carat ruby than a 1 carat ruby. Therefore, not only is the total price higher, but the price per carat is also higher because of the added rarity factor. For example, a 1 carat ruby of excellent quality might cost $1000. A 5 carat ruby of the same quality would NOT cost $5000 (5 X 1), rather it might cost $10,000. Here is a comparison of rubies. They have similar color, so we can see how their size affects their value. Note: We are comparing only the main stones, not their settings.
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| Very small: Rubies of this size are not rare. By themselves, they would be worth less than $100. | Average: This size ruby (about 1 ct.) is more valuble but still easy to find. It would cost about 2 or 3 times the value of the stones to the left. | Large: Rubies this size (over 3 carats) are very rare. A stone of this size can cost between 7 and 10 times the price of the one before. | Very Large: Rubies of this size (over 7 carats) usually belong to queens or in museums. The price of one would be 2 to 4 times the value of the previous ruby. |
Hi,
I’m interested in rubies, here it says that very large rubies usually belong to queens or in museums. I have a large ruby over 8 ct that is original and has no treated. How can I determine officially its quality and price?