Gold's weight or purity is measured in Karat. A high Karat gold signifies the high purity of gold. The different purity of gold is used to make various gold-based items such as bars, coins, jewelry, etc. Here's a detailed guide that will help you understand the difference between 24K, 22K, and 18K gold:
24K gold
A 24 Karat gold is 100 percent pure gold and does not have mixed metal. It is known as 99.9 percent pure in the local market and has a distinct bright yellow color. The 24 karat gold is more expensive than 22 or 18 Karat gold. It is soft and pliable, and that's why not used in making regular forms of jewelry.The 24K gold is used to make coins bars and used in
electronics and medical devices.
22K gold
The 22 Karat gold is mostly used in making jewelry. In 22K gold, 22 parts of the metal are gold. The rest two comprise metals like silver, zinc, nickel, and other alloys. It is also known as 91.67 percent pure gold. Mixing alloys makes the texture of gold harder, and hence jewelry becomes durable.
18K gold
The 18 Karat gold comprises 75% gold mixed with 25% of other metals such as copper, silver, and other alloys. This type of gold is used to make stone studded jewelry and other diamond jewelry. It is less expensive compared to 24K and 22K gold. All the gold coins, bars, or jewelry have their purity marked into it. It would be best always to buy jewelry that has Hall Mark and purity inscribed on them.