Question

The percentage of gold in 24-carat gold is:
(A) 99.99
(B) 91.6
(C) 75
(D) 95

Answer 1

Hint: The weight of fine metal therein, in proportion to the total weight which includes alloying base metals and any impurities, is known as the ‘fineness’ of a precious metal object.

Complete step by step solution:-Alloys are added to pure metals that lack hardness and make it durable for coins and jewellery. Adding alloys also alters colours and decreases the cost per weight. For example, copper is added to precious metal silver to make it a more durable alloy for making coins, hardware, and jewellery.
-A system denoting the purity of platinum, gold, and silver alloys by parts per thousand of pure metal by mass in the alloy is known as Millesimal fineness. For example, ‘750’ means an alloy containing 75% gold.
-The Millesimal fitness of precious metal gold is associated with the following terms-
(i) 999.999- which is ‘six nines fine’ is the purest gold ever produced.
(ii) 999.99- which is ‘five nines fine’ is the second purest gold type and is currently being produced.
(iii) 999.9- which is ‘four nines fine’ is the most popular gold.
(iv) 999- which is ‘three nines fine’ and is also known as 24 karat gold.
(v) 995- is the minimum allowed gold in good delivery gold bars.
(vi) 990- which is ‘two nines fine’
(vii) 986- which is Ducat fineness. The Ducat gold or silver coin is used as a trade coin in Europe from the later Middle Ages.
(viii) 958.3- which is known as 23 karat gold.
(ix) 916- which is known as 22 karat gold was historically the most widely used fineness for gold bullion coins.
(x) 900- which is ‘one nine fine’
(xi) 834- which is known as 20 karat gold
(xii) 750- which is known as 18 karat gold
(xiii)625- which is known as 15 karat gold
(xiv)583.3- which is known as 14 karat gold
(xv) 417- which is known as 10 karat gold

So, the correct answer is option (A).

Note: You may get confused between 24 karat gold, 22 karat gold, or 18 carats gold. The 24 karat gold is the purest gold among these three and has a distinct yellow colour. The 24 karat gold is more expensive than the other two gold, but it is so soft and pliable that it can’t be used in making regular forms of jewellery. The 22 karat gold is mostly used in making jewellery as it has 22 parts of the metal and the rest two comprises metals like silver, zinc, nickel, and other alloys that provide durability and hardness to it. The 18 karat gold comprises 75% gold mixed with 25% of other metals and is used to make stone studded jewellery and diamond jewellery. 18 karat gold is the cheapest among the other two types.