Gems & Gold Weight and Pricing
Gems Weight Units
Carat – is the unit used to express the weight of gemstones, with one carat equal to 200mg of actual weight.
Gram – is a weight unit that is used for less expensive and rather small gems.
Grain – is used to weigh pearls. It is equal to 14 of the carat, i.e. 50mg. It is seldom used nowadays.
The centers of the jewelry’s business had their own mass measures.
So, the London carat was equal to 205,3mg, the Florentine one – 197,2mg. It explains the difference in the weight of historical diamonds. The metric carat was introduced in 1907 in Paris. It is equal to 200mg. That is what we have now.
How to Calculate the Price of a Gemstone
In the gems trade the price of 1 carat is indicated. If you want to calculate the full price of a stone you should not multiply the price of a carat by the stone weight in carats. The price of a carat rises progressively with the increase of the stone size. Say, if a diamond weighing less than 1 carat costs X, a diamond with the mass of 2 carats doesn’t cost 2X, but much more.
Gold
Yellow Gold – the gold’s natural color and is the most common gold used for jewelry
White Gold – It differs from yellow gold by addition of alloys. Usually they are palladium or nickel, zinc and cooper.
Rose gold – is made by alloying gold with cooper, which gives it a beautiful pink color.
24 karat = 100% gold
Too soft for jewelry
22 karat = 91.7% gold
Very soft — not recommended for jewelry
18 karat = 75.0% gold
Recommended for fine jewelry
14 karat = 58.3% gold
Recommended for jewelry
12 karat = 50.0% gold
Not acceptable for jewelry
10 karat = 41.7% gold
The legal karat limit considered as real gold in the United States
How to Calculate the Price of gold
The price of gold jewelry depends on the jewelry design, purity of gold or karat weight and amount of the material needed for this particular item.
Do you wear religious symbols made of gold? Do you have a cross around your neck or a Star of David on your wrist? You are not alone. Religious gold symbols are a major part of the gold business and an important part of people’s lives.



