Gold Design Gold Purity and Alloys

Question 1

What does the hallmark '750' stamped on gold jewelry indicate?

Accepted Answer

75% pure gold, equivalent to 18 karats

Answer

The hallmark 750 indicates 750 parts per 1,000 are pure gold, which is 75% gold purity — the European marking for 18 karat gold.

Question 2

Which alloy is typically added to yellow gold to create 14k gold?

Accepted Answer

A mixture of copper, silver, and zinc

Answer

14k yellow gold alloy typically contains gold mixed with copper, silver, and sometimes zinc to achieve 58.3% gold content.

Question 3

What gives rose gold its distinctive pinkish-red color?

Accepted Answer

A higher proportion of copper in the alloy

Answer

Rose gold's characteristic warm pink color comes from a higher concentration of copper in the gold alloy — typically around 25% copper in 18k rose gold.

Question 4

Which karat gold is considered 'pure' gold and contains no other metals?

Accepted Answer

24 karat

Answer

24 karat gold is 99.9% pure gold with no significant alloying metals — the highest purity commercially available.

Question 5

Why is 24k gold rarely used for everyday jewelry in the US despite being the purest?

Accepted Answer

It is too soft and malleable, making it prone to scratching and bending easily

Answer

24k gold's softness (Mohs 2.5) means it bends, scratches, and deforms easily in everyday wear — alloyed golds are far more durable.

Gold Design Practice Test

Gold Design Practice Test

Gold Design Gold Purity and Alloys