HELPFUL TIPS ABOUT GOLD
In an alloyed state, gold is soft, very malleable, ductile and of bright yellow color in its pure state.
Using it for fine jewellery in its pure form is not practical, because it is too soft and can be easily deformed or bruised. However, it can be hardened or change its color by alloying it with other metal.
Alloying is the process of mixing other metals with pure gold, namely silver, copper and zinc to make it hard and more malleable. Once gold is alloyed, it is measured in terms of karat.
Karat is the unit of measurement in determining the quantity of gold in an alloy and symbolizes by the letter ‘K’.
A 24 karat gold, technically is not 100% pure gold, and the highest purity of a gold piece can only be 999 or 99.9% purity, which is a government controlled gold bars. However, in some jewelleries such as gold rings, it has 99.95% purity.
Changes in color of gold is due to infusion of other metals.
Determining the gold content in a piece of gold bar:
To determine the amount of percentage of pure gold which an alloy contains, the following formula is used:
KARAT divide by 24 Thus:
24K / 24 = 1.00 or 100%
22K / 24 = 0.917 or 91.7 %
20K / 24 = 0.833 or 83.3 %
18K / 24 = 0.750 or 75.0%
14K / 24 = 0.583 or 58.3 %
12K / 24 = 0.500 or 50.0 %
10K / 24 = 0.417 or 41.7 %
8K / 24 = 0.333 or 33.3 %
6K / 24 = 0.250 or 25.0 %
Gold is measured according to the international unit for weight measure called TROY OUNCE which is equivalent to 31.1035 grams.
How to determine the amount of pure gold in a piece of ‘gold bar’?(Note: It is assumed that the gold bar is not fake)
1. Determine the precise karat of the gold bar.
2. Divide the karat to 24
3. The quotient will give the percentage of gold in the bar.
Example:
1. 22K divided by 24K = 0.917
2.
APPLICATION:a. A gold bar with a weight of 500 grams was assayed at 22K and gives gold percentage of .917 or 91.7%.
b. To find the amount of gold at 24K, multiply .917 by 500 grams and it will give you the weight of 458.5 grams.
c. Therefore, 458.5 grams in 24K is the amount of pure gold in a bar of 500 grams.
d. Subtracting 458.5 grams from 500 grams will give us 41.5 grams of other METAL.
Angel