Free mixed-karat lot calculator
Value a mixed lot of gold jewelry before you bid.
Estate lots, pawn lots, and auction trays often mix several karats. Enter each sorted pile separately so 10K, 14K, 18K, 22K, and 24K gold are valued at their own purity. The calculator totals the estimated fine-gold weight and melt value for the whole lot.
You can also add the asking price, buyer's premium, shipping, tax, and other costs. The final comparison shows whether the full buying cost is below, near, or above the metal estimate—not whether the jewelry is genuine or guaranteed to be profitable.
Calculate the whole lot.
Sort the pieces by verified karat first. Weigh each karat group, then subtract stones, watch movements, steel springs, weighted sections, and other non-gold material from that same group. Leave an uncertain pile out until its metal and weight can be checked.
Looking for lots instead of valuing one you already found? SpotMelts members can search the catalog and sort priced listings by price-to-melt ratio. See membership pricing.
Why the lot needs separate karat piles.
A ten-gram 10K pile contains about 4.17 grams of gold. A ten-gram 18K pile contains 7.5 grams. Treating both as an average karat can move the estimate enough to turn a seemingly cheap lot into an expensive one. If a piece has no trustworthy mark or test, its purity is unknown.
Gold-plated, gold-filled, rolled-gold, and vermeil pieces are not solid karat gold throughout. Their full weight should not be entered under the surface mark. A recognized maker, an antique piece, or a valuable stone can also be worth more intact than its metal content.
Use the full cost, not the current bid.
Auction buyer's premiums are added to the hammer price, and tax may apply to the premium as well as the bid. Shipping, insurance, testing, refining, and selling costs can erase a narrow discount. Recalculate from the final price before committing to a purchase.
For one item, use the gold melt-value calculator. To understand the comparison itself, read the price-to-melt guide. If you need to work backward from premiums, tax, shipping, and fees, calculate your maximum hammer bid. If you are searching for listings, the near-melt buying guide shows the checks in order.