How the calculator works
Bullion is priced on its pure metal content, not its gross weight. A 1g sterling silver chain contains only 0.925g of silver; an 18k gold ring is 75% gold. The calculator multiplies your weight by the purity, converts to grams, then multiplies by the live per-gram spot price in GBP.
Purity quick reference
- Gold: 24k = 999.9 fine, 22k = 916, 21k = 875, 18k = 750, 14k = 585, 9k = 375
- Silver: Fine = 999, Britannia = 958, Sterling = 925, Coin = 900
- Platinum / Palladium: commonly 999 or 950
What you actually get from a dealer
Spot is the wholesale benchmark. Dealers pay a percentage below spot when they buy scrap (the spread covers refining + margin) and sell coins/bars at a premium above spot. Always get a quote from a regulated UK bullion dealer before transacting.