Some Interesting Facts About Gold And Its Purity

First some background:

Elements make up minerals. There are 118 natural elements; 94 of these are natural and 24 are synthetic.

Minerals are naturally occurring crystalline substances.

Traditional definitions say that minerals have to be inorganic, but there are also organic minerals (biominerals) [examples: bones and teeth].

Nearly all minerals are combinations of elements.

 

     Examples: halite (ordinary table salt) consists of sodium and chlorine

             Pyrite (“fools gold”) consists of iron and sulfur

            Quartz consists of silicon and oxygen

Minerals consisting of pure (native) elements are rare.

            Metallic examples: gold, silver, copper

            Non-metallic examples: carbon (coal, graphite, or diamonds)

         

Now, let’s talk about gold:

Close-up view of crystals of leaf gold, field of view 1.5 mm width

Gold is measured in karats (K). A karat is defined by its degree of purity. Pure gold is 24K.

24K gold = theoretically 100%, but some sources describe the purity as only 99.9%

22K = 91.6 (i.e., divide 22 by 24 = 91.6%)

18K = 75%

14K = 60%

12K gold = 50%

10K = 41.6%

1K= 4.1%

24K gold is very soft; it tends to bend or scratch easily. In order to make gold harder for making jewelry, gold is alloyed with copper, silver, or other elements. When alloys are added, the purity of gold decreases correspondingly.