What does the ounce label measure?
1 troy oz = 31.1034768 g
This conversion uses troy ounces. Check whether the product document gives gross weight or fine-metal content. Do not apply fineness again to a weight already stated as fine content.
Troy ounces and ordinary ounces differ
A precious-metal troy ounce is exactly 31.1034768 grams. An ordinary ounce is approximately 28.3495 grams. Using the wrong ounce introduces a systematic error between weight and price. When a coin is already described by fine metal content, do not apply purity to that fine quantity again. Gross weight and fine content are different starting points.
A worked valuation
The following figures are a worked example, not current prices. Illustrative USD/troy-ounce reference: 3,100. 0.25 troy ounces × 1 = 7.7759 grams of fine gold. Illustrative metal value: 775 USD.
This value is neither a dealer’s ask nor your net resale proceeds. Enter actual bid and ask quotes in the same unit and add total fees separately. Quotes taken at different times can also differ from a calculated reference. When changing currency in the calculator, remember that FX is a daily reference.
Separate the product premium
Fabrication, minting, branding and packaging can add to a product’s price. Paying a premium does not establish that it will be recovered on resale. Compare fine content and total transaction cost rather than gross grams alone. Use the dealer ask when purchasing and the dealer bid when reselling.