Gold (Au)
General Info
Gold is soft, dense metal that is naturally yellow, though color may vary depending on alloy components.
Quick Facts
| Type(s) | Transition Metal, Precious Metal | |
| Melt | F | 1945 |
| C | 1063 | |
| MOHS | Lower | 2 |
| Upper | 2.5 | |
| Annealing | Heat to a dull red then quench when red is gone | |
| Conductivity | Conductive | |
| Ferrousity | Nonferrous (non-magnetic) |
Composition
Gold can be found as almost pure, or can be combined with other minerals and compounds to make alloys. Mineral and compounds are across the top of the table, and the associated alloys are shown along the leftmost column.
| Gold and Some Common Alloys | Gold (Au) | Silver (Ag) | Copper (Cu) | Nickel (Ni) | Indium (In) | Aluminum (Al) | Cobalt (Co) | Iron (Fe) | Whiteners (Ni or Pd or Both) | Other |
|---|---|---|---|---|---|---|---|---|---|---|
| Gold, 24K, Fine, Pure | 99.9% | |||||||||
| YELLOW | ||||||||||
| Yellow Gold, 18K | 75% | 12.5% | 12.5% | |||||||
| Yellow Gold, 18K | 75% | 10% | 15% | |||||||
| Yellow Gold, 14K | 58.3% | +/- | ||||||||
| Yellow Gold, 12K | 50% | 25% | ||||||||
| Yellow Gold, 10K | 41.7% | +/- | ||||||||
| WHITE | ||||||||||
| White Gold, 14K | 58.5% | |||||||||
| White Gold, 14K | 58.5% | |||||||||
| White Gold | ||||||||||
| White Gold | ||||||||||
| White Gold | 90% | 10% | ||||||||
| White Gold, 9K | 37.5% | 62% min | 0.5% (unspecified) | |||||||
| White Gold, 9K | 37.5% | 45% min | 17.5% (unspecified) | |||||||
| OTHER COLORS | ||||||||||
| Black Gold, 18K | 75% | 25% | ||||||||
| Blue Gold, 18K | 75% | 25% | ||||||||
| Blue Gold | 46% | --- | 54% | |||||||
| Electrum | 73% | 27% | ||||||||
| Pink Gold, 18K | 75% | 5% | 20% | |||||||
| Purple Gold | 80% | 12.5% | 20% | |||||||
| Red Gold, 18K | 75% | 12.5% | 12.5% | |||||||
| Red Gold | 50% | 50% | ||||||||
| Rose Gold, 18K | 75% | 2.75% | 22.25% |
Footnotes
https://www.ganoksin.com/article/different-coloured-gold-alloys/
https://en.wikipedia.org/wiki/Colored_gold
https://theassayoffice.com/white_gold_labexpert