The use of pure precious metals in jewelry is not always justified and convenient due to its high cost, physical and chemical characteristics, for example, insufficient hardness and wear resistance.
To give gold jewelry more hardness and wear resistance, alloys with other metals are used, which are called ligatures. They are added in certain proportions to gold to obtain the desired properties of the alloy. The best alloys are silver and copper, because these metals enhance all the physical characteristics of the alloy. Pure gold is used very rarely, as it is too soft, easily deformable, and scratched. Alloys can be precious and non-precious metals, although alloys are called precious in any case.
The following metals can be used as alloys for gold alloys: silver, copper, palladium, nickel, platinum, cadmium and zinc. Each of the components affects the properties and color of the alloy in its own way. Using different gold alloys, products with multicolored decorations are obtained.
Silver gives the alloy softness, malleability of gold, reduces the melting point and changes the color of gold. As silver is added, the color of the alloy turns green, turning yellow-green; with a silver content greater than 30%, the color turns yellow-white and fades as the amount of silver increases; when the alloy contains 65% silver, the color of the alloy turns white.