Treatment status is a major pricing factor. Untreated gems of fine color and clarity command significant premiums—unheated Burmese rubies or Kashmir sapphires can be worth many times more than heated equivalents. Heat-treated stones are common and trade at standard market levels for their quality.
Fracture-filled or heavily diffused gems receive the largest discounts due to durability concerns and lower perceived rarity. Irradiated or coated stones also sell lower. Buyers rely on laboratory reports stating treatment details to assess true value. Transparent disclosure allows informed comparison across similar-looking stones.