Cut, relatively clear garnets sell for about $5 a carat retail. Wholesale about $1.50 a carat.
If you have a rare garnet like a good sized Tsarovite you could get more. Very unlikely that you will find one of any size - they really are rare.
Garnets are very common worldwide. The cost of the cut "gem" is more about the cost to cut it than about the value of the rough stone. If you can cut garnets yourself and you have a ready supply of quality garnet rough you could
get prices like this. I seriously doubt you could pay for materials much less labor at those prices.
John had the best idea to get value for garnets.

Sell them as part of the natural gems you found with the gold you are selling.
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