Creating black gold involves processes that alter the surface color of yellow gold.
The process of producing black gold typically involves treating the surface of yellow gold to achieve a darkened appearance. Based on the provided reference, two methods are mentioned: oxidation and femtosecond laser treatment.
Oxidation Method
One common method is oxidation. In this process, an acid is applied to the surface of the yellow gold. This chemical treatment causes the surface layers of the gold to oxidize, effectively turning it black.
However, this specific process is noted to have a significant drawback:
- Applying acid to the surface of yellow gold, while achieving the black color, weakens the metal.
- This weakening makes the material less desirable for durable jewellery.
Femtosecond Laser Treatment
A more advanced and durable technique for producing black gold involves using femtosecond laser treatment. While the reference doesn't detail the exact mechanism, it highlights that this method is considered:
- A more advanced process compared to oxidation.
- Results in a durable black finish, unlike the acid treatment.
In summary, black gold color can be achieved through surface treatments like acid-induced oxidation (though less durable) or advanced laser techniques.
