Green gold alloys are made by leaving the copper out of the alloy mixture and just using gold and silver. It actually appears as a greenish-yellow rather than green. Eighteen karat green gold would therefore contain a mix of 75% gold and 25% silver (or 73% gold and 27% silver). Fired enamels adhere better to these alloys.
Green gold was known to Lydians as long ago as 860 BC under the name electrum, a naturally-occurring alloy of silver and gold.
Cadmium can be added to gold alloys in amounts of up to 4% to achieve a green color. The alloy of 75% gold, 23% copper, and 2% cadmium yields light-green 18-karat gold. The alloy of 75% gold, 15% silver, 6% copper, and 4% cadmium yields a dark-green alloy. Cadmium is, however, highly toxic.
Read more about this topic: Red Gold
Famous quotes containing the words green and/or gold:
“Meanwhile the mind from pleasure less
Withdraws into its happiness;
The mind, that ocean where each kind
Does straight its own resemblance find;
Yet it creates, transcending these,
Far other worlds and other seas,
Annihilating all that’s made
To a green thought in a green shade,”
—Andrew Marvell (1621–1678)
“In our daily intercourse with men, our nobler faculties are dormant and suffered to rust. None will pay us the compliment to expect nobleness from us. Though we have gold to give, they demand only copper.”
—Henry David Thoreau (1817–1862)