Mixing Metals

Alloys

Metallurgists have long modified gold's properties by alloying, or mixing, it with other metals to meet aesthetic and technological needs. Melting gold with other metals both hardens it and changes its color. Gold alloys can also be blue, purple, and brown.

Colors of Gold:


Yellow: 75% gold, 16% silver, 9% copper	White: 75% gold, 17% palladium, 4% silver, 4% copper	Green: 75% gold, 25% silver

Pink: 75% gold, 25% copper	Black: gold plus rhodium or ruthenium

Karats

The proportion of pure gold in an object is measured in karats, a unit initially based on the weight of dried carob seeds. One karat is 1/24th of the total weight of the object. Therefore, 100 percent pure gold is 24 karats.

Weights of Gold:


22K: 91.6% gold	20K: 83% gold	18K: 75% gold

14K: 58.3% gold	10K: 41.67% gold