Gold is a precious metal, with a high degree of ductility and malleability, that is used in the manufacture of a wide range of products including jewelry, electronics, and coinage.

Gold, through mixing in varied alloys, comes in an array of colors, including white, rose, green, and purple.  The most popular color, white gold, is made by adding nickel, copper, and zinc.

PERCENT
(parts per 100)

100    percent
91.7  percent
75.0  percent
58.3  percent
41.6  percent

FINENESS
(parts per 1000)

999 fine
917 fine
750 fine
583 fine
416 fine

KARATS
(parts  per 24)

24 karat
22 karat
18 karat
14 karat
10 karat

 

Gold Filled: Also called gold overlay, a layer of at least 10-karat gold permanently bonded by heat and pressure to one or more surfaces of a support metal, then rolled or drawn to a prescribed thickness. The karat gold must be at least 1/10 by weight of the total metal content.

Rolled Gold Plate: Material consisting of a layer of plating of 10-karat gold or better which is mechanically bonded to a base metal. The karat gold content may be less than 1/20 but must be properly identified by weight in terms of total metal content.

Vermeil: Gold at least 15- micro-inches thick, bonded to sterling silver by an electrolytic or mechanical process.

Gold Leaf: Pure gold that is pounded into sheets applied to other surfaces by hand. Usually about 3 micro-inches thick.