The carat (abbreviation ct or K) is a measure of the purity of gold and platinum alloys. In the United States and Canada, the spelling karat is used, while the spelling carat is used to refer to the measure of mass for gemstones.
24-carat gold is pure (100% Au w/w), 18-carat gold is 75% gold, 12-carat gold is 50% gold, and so forth.
Historically, in England the carat was divisible into four grains, and the grain was divisible into four quarts. For example, a gold alloy of fineness (that is, 99.2% purity) could have been described as being 23-carat, 3-grain, 1-quart gold.
The most common carats used for gold in bullion, jewellery making and by goldsmiths are:
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24 carat (millesimal fineness 999)
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22 carat (millesimal fineness 916)
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20 carat (millesimal fineness 833)
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18 carat (millesimal fineness 750)
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15 carat (millesimal fineness 625)
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14 carat (millesimal fineness 585)
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10 carat (millesimal fineness 417)
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9 carat (millesimal fineness 375)
Terminology
22/22K - a quality mark indicating the purity of gold. The first 22 signifies the "Skin purity" of gold jewellery and the second 22 signifies that after melting purity of the gold jewellery will be 22K (22 Karat) or 91.67% of pure gold. This symbol or stamp is very popular on the gold jewellery business in Asian countries like India, Pakistan, Bangladesh, Nepal, Yemen, and Gulf Countries.
This practice was pioneered and introduced in the early mid-1980s by Nemichand Bamalwa & Sons of Kolkata, India, sparking a revolution in India as it forced jewellers to indicate correctly the after-melting purity, and heightened consumer awareness made it a most sought-after stamp or quality mark.
24-carat gold is pure (100% Au w/w), 18-carat gold is 75% gold, 12-carat gold is 50% gold, and so forth.
Historically, in England the carat was divisible into four grains, and the grain was divisible into four quarts. For example, a gold alloy of fineness (that is, 99.2% purity) could have been described as being 23-carat, 3-grain, 1-quart gold.
The most common carats used for gold in bullion, jewellery making and by goldsmiths are:
*
24 carat (millesimal fineness 999)
*
22 carat (millesimal fineness 916)
*
20 carat (millesimal fineness 833)
*
18 carat (millesimal fineness 750)
*
15 carat (millesimal fineness 625)
*
14 carat (millesimal fineness 585)
*
10 carat (millesimal fineness 417)
*
9 carat (millesimal fineness 375)
Terminology
22/22K - a quality mark indicating the purity of gold. The first 22 signifies the "Skin purity" of gold jewellery and the second 22 signifies that after melting purity of the gold jewellery will be 22K (22 Karat) or 91.67% of pure gold. This symbol or stamp is very popular on the gold jewellery business in Asian countries like India, Pakistan, Bangladesh, Nepal, Yemen, and Gulf Countries.
This practice was pioneered and introduced in the early mid-1980s by Nemichand Bamalwa & Sons of Kolkata, India, sparking a revolution in India as it forced jewellers to indicate correctly the after-melting purity, and heightened consumer awareness made it a most sought-after stamp or quality mark.