14/05/2019
Before we buy we need to understand ;
What is 18K Gold?
18 Karat Gold is not Pure Gold. It is an alloy in which of every 24 karats mass, 18 karats are gold. The remaining are other materials. Most jewelry, industrial and medical grade gold items “are not pure gold” gold. They are alloys with high gold content. How much of the mass of the material is actually pure gold is called its “Fineness”. Thus 18K gold is 18K fine.
18 Karat Gold Fineness Calculations
The fineness of 18K gold can be expressed, based on karat (or karetege), percentage, or parts per one thousand (ppt). Here is the reasoning. In 18K gold, 18 karats are gold, 7 karats are not gold. Thus, from this fact we can derive the following:
18K Gold means that 18 parts out of 24 are pure gold and 7 parts out 24 parts are other materials
Based on this fact, we can derive the 18 karat fineness expressed as percentage(%) and as parts per one thousand (ppt). This is how it works
18 karat divided by 24 karat equals 0.750 (18K / 24K = 0.750). If you multiply this by one hundred (100) you get 75.0. This means that 18 Karat (18K) gold is 75 percent gold, the rest other materials. Another way of expressing it is 18 karat gold is 75% fine, or has a fineness of 75%.
18 karat divided by 24 karat equals 0.75 (18K / 24K = 0.75). If you multiply this by one thousand (1000) you get 750. This means that 18 Karat (18K) gold is 750 parts per one thousand (1000) gold. The rest other material. Another way of expressing it is 18 karat gold is 750 parts per one thousand (ppt) fine, or has a fineness of 750.