K, KT, CT are the gold abbreviations that stand for Karats (the USA) or Carats. This measurement describes the gold purity. Pure gold is 24K and has a bright yellow color. Pure gold is the most expensive: The lower the karat number, the less gold there is in the alloy, and thus the lower the price. Though it has been mined from the earth since ancient times and was long used as a medium of exchange, people don’t usually make jewelry items from pure gold. Instead, most gold items are made up of a mixture of gold with other metals.
There are two main reasons.
Pure gold is more expensive than alloys, and most people would not be able to afford to wear jewelry every day.
Gold is an incredibly soft and moldable metal which can be easily scratched or damaged. So, the alloys make pure gold stronger and more durable. That’s how yellow, white, and rose gold appeared.
Pure gold is strengthened in a combination of such metals as copper or zinc. The amount of gold in the alloy influences the strength, color, and the price of the metal. The purity of gold is specified in karats, which refers to the amount of gold in the alloy. For example, to make the gold white, pure gold is mixed with metals such as palladium, silver, or nickel. The finished product is coated with rhodium.
Many people have noticed that while gold is a little more expensive than yellow gold. There are several reasons for that:
In the 1990s, the popularity of yellow gold decreased and was considered out of fashion. The cooler look of metals such as platinum and white gold enjoyed new-found fame. For instance, white gold is currently more in demand than yellow, so, some jewelers may charge more.
Unlike yellow gold, white gold needs rhodium plating to make it more durable and to produce the gleam that white gold is known for. Depending on the size of the item, rhodium plating can add an extra $50-$100. Besides, it’s worth noting that this is not a one-time expense. You’ll probably need a fresh rhodium layer every 2-3 years, as rhodium plating tends to wear down, especially if you wear the jewelry item regularly.