Gold purity is a measure of the amount of gold present in a particular object or material. It is usually expressed as a percentage or in karats. The karat system is commonly used in the United States, while the rest of the world uses the metric system.
Pure gold is 24 karats, meaning it is 100% gold. However, pure gold is generally considered too soft for use in jewelry, so it is often alloyed with other metals to increase its strength and durability.
Common gold alloys used in jewelry include 18 karat (75% gold), 14 karat (58.5% gold), and 10 karat (41.7% gold). The purity of gold can be measured using various techniques, including acid testing, X-ray fluorescence, and fire assay.
It is important to note that the purity of gold can affect its value. Generally, the higher the karat, the more valuable the gold. However, other factors such as the weight, rarity, and craftsmanship of an object can also affect its value.