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:
“Among the Indians he had fought;
And with him many tales he brought
Of pleasure and of fear;
Such tales as told to any Maid
By such a Youth, in the green shade,
Were perilous to hear.”
—William Wordsworth (1770–1850)
“Perfect alchemists I keep who can transmute substances without end, and thus the corner of my garden is an inexhaustible treasure-chest. Here you can dig, not gold, but the value which gold merely represents; and there is no Signor Blitz about it.”
—Henry David Thoreau (1817–1862)