Things You'll Need
Instructions
Examine the gold ring with a jeweler's loupe or magnifying glass for any markings.
Look for a numbered stamp on the inside of the ring. If the jewelry is stamped with three digits, such as 417 in the case of a 10-karat gold ring, put a decimal point after the second number to find out the percentage of gold in the piece.
In this case, the gold ring is 41.7 percent gold. To put it another way, it is 10/24 pure gold or 10 karat.