Pure Gold

The best-known precious metal. Throughout history, gold has been a symbol of wealth and royalty, and thus the word "gold", by implication, is used to describe anything valuable and rare, such as a heart of gold, golden hands, the golden age, and black gold.
In its raw natural state, gold is a soft, shiny, yellow metal. In order to utilize it, the pure gold must be mixed with other metals, such as palladium, platinum, silver, copper and nickel, which harden it, determine its hue, and produce various degrees of purity:
24 karat – contains 99.99% pure gold, hence its name: four nines fine.
22 karat – contains 91.6% pure gold and 8.4% other metals.
21 karat – contains 87.5% pure gold and 12.5% other metals.
18 karat – 75% pure gold
14 karat – 58.5% pure gold
9 karat – 37.5% pure gold
Red gold – mixed with copper, which has a reddish tint.
White gold – mixed with pale metals like nickel or platinum.
Yellow gold – in order to maintain its yellow color, it’s mixed with palladium, copper and silver.
In Israel, the verification mark for the various degrees of gold purity is a David's Harp.
Pure gold has many uses in a variety of fields:
Manufacturing jewelry and other fine items.
Medals.
Coins.
The electronics and computer industries.
Nanotechnology.
Medicine.