Many ask us what is that of green gold. Perhaps we are more accustomed to talking about rose gold and, of course, white gold; however gold is already used in jewelry in many more colors. The coloratura that acquires the gold, in essence yellow, varies of the metal or metals with which it is alee.
The gold we use in jewelry is usually 18kt, because it is the first law; although there is also lower, and higher (24 kt fine gold) but this is rarely used because it is excessively malleable and in jewelry it is usually necessary to increase its hardness and durability, so we mix it with other metals.
If we want to keep gold yellow, we mix it with silver and copper, if we want it to be white we will do it with silver plus palladium or platinum, if we wanted it pink we would put in addition to silver much more copper than we used to the yellow, and in the case of wanting it green, we mix it exclusively with silver. Adding Cadmium to gold and silver would get a more intense green; but we do not use it because it is highly toxic and, because aesthetically, we do not seek to obtain a green, but rather to kill the yellow straw of the gold, conserving its brightness. That is, we get a more subtle, paler or whiter yellow, which is what we like for our pieces of contemporary jewelry. Of course not all the yellow golds are the same, nor the roses ... Neither of course the greens. Each jeweller has its own formula and the proportion and combination in which metals are alloyed turn out to be personal recipes of each founder.
We work our pieces, basically, with silver bathed in green gold. We always do it with the same gilder because it gives the exact tone we look for.
Find the differences among the different shades of gold presented by the brands of jewelry, and you will see how you discover a world where you will like some much more than others.