GOLD ALLOYS

Pure 24K gold has no alloys mixed in, and is bright yellow in color. Alloys which are mixed 18 parts gold to 6 parts alloy create 18K gold, 14 parts of gold to 10 parts of alloy create 14K, 10 parts of gold to 14 parts of alloy create 10K, etc. The parts of gold plus the parts of alloy add up to 24. The higher the karat number the more pure the gold alloy should be.

Gold coins and gold jewelry are made up of gold alloys that are mixtures of gold with other metals. Alloys are added to make the gold stronger, color the gold, or to make the gold less expensive for the buyer or seller.

Yellow Gold

Proof gold is 99.99% gold and used only for standards purposes

24K gold: 99.7% pure gold

22K gold: 91.67% gold, 5% silver, 2% copper and 1.33% zinc

18K gold: 75% gold

14K gold: 58.3% gold

10K gold: 41.7% gold

The balance of the gold alloy may be made up of silver, copper, tin, iron, zinc or other metals.

Gold can also be developed into various colors. These colors are generally obtained by alloying (mixing) gold with other metals.

White Gold

18K White Gold: 75% yellow gold and 25% platinum or palladium

18K White Gold may also be 75% yellow gold, 10% palladium, 10% nickel, 5% zinc
Avoid this alloy if sensitive to nickel allergies

18K Red Gold: 75% yellow gold and 25% copper

18K Rose Gold: 75% yellow gold, 22.25% copper and 2.75% silver

18K Pink Gold: 75% yellow gold, 25% copper and 5% silver

18K Gray White Gold: 75% yellow gold, 17% iron, 8% copper

18K Soft Green Gold: 75% yellow gold, 25% silver

18K Light Green Gold: 75% yellow gold, 23% copper, 2% cadmium

18K Green Gold: 75% yellow gold, 20% silver, 5% copper

18K Deep Green Gold: 75% yellow gold, 15% silver, 6% copper, 4% cadmium

18K Blue Gold: 75% yellow gold, 25% iron

18K Purple Gold: 80% yellow gold, 20% aluminum


High-end flutes are often made of solid rose gold. The most common rose gold alloy for this is 14K, but 9K, 10K, 18K and 19.5K are also available from the major flute makers.

The Federal Trade Commission (FTC) of the United States has standardized the karat markings used within U.S. boundaries. Items 10-karat or greater are to be stamped with either "K" or "Kt." Decimal markings are also an option under the CFTC regulations.

Under-karating is against the law in the United States of America. There are specific mandated consequences including fines, etc., based upon the severity of the infractions.

Caveat emptor, let the buyer beware…