What is 18K gold?
18-karat gold contains 75% pure gold and 25% alloy metals. It has more gold content than 10K or 14K and is commonly used in fine jewelry, luxury watches and wedding jewelry.
18K and 750 hallmarks
Typical marks include “18K,” “18KT” and “750.” The 750 mark represents 750 parts of gold per thousand. White, yellow and rose 18K gold use the same nominal gold percentage even though their alloy metals differ.
How the per-gram value is estimated
18K value per gram = pure-gold price per gram × 0.750
Because 18K contains more pure gold, its estimated metal value per gram is higher than 14K at the same market reference.
Before selling 18K jewelry
Fine jewelry may command more than scrap value when its brand, condition, design or stones are desirable. Separate a melt-value estimate from an appraisal of the complete piece.
If the item is signed by a known maker or contains documented stones, consider a jewelry specialist or auction estimate before accepting a scrap offer.