Is 9ct gold harder than 18ct gold?
The answer is simply no. Metal hardness is measured by what is called the Vickers scale where harder metals receive a higher Vickers score than less hard metals. 9ct gold has a Vickers hardness ranging from 80 – 120, according to the composition and condition. 18ct gold has a Vickers hardness ranging from 135 – 165 (both in the annealed condition). This shows 18ct gold as harder.
