According to the second edition of the Standard Catalog of Gem Values, wholesale prices for faceted gem rubies range from $100 to $15,000 per carat. Wholesale prices vary based on color, size, origin and clarity.
According to a price survey by the International Gem Society, clean, top-color rubies with a size range of 1/2 to 1 carat sell online at retail prices between $1,000 to $3,000 per carat. Rubies are the most valuable gems of the corundum family. In fact, large rubies can be more valuable than diamonds of the same size and are actually rarer. Ruby is the birthstone for the month of July.