Created by German mineralogist Friedrich Mohs in 1812, the Mohs scale of hardness serves as a vital tool for mineral identification. Comprising 10 distinct minerals ranging from the softest (talc) to the hardest (diamond), this scale proves particularly valuable in jewellery making by helping determine suitable applications for gemstones:

i.e. Will a particular gemstone withstand daily wear in ring form?

Is it safe to place different gemstones adjacent to one another without risk of damage?

The fundamental principle is that each mineral on the scale can scratch those ranked below it, while being susceptible to scratching by those ranked above.

Therefore, diamond, being the hardest mineral, can scratch all minerals ranked 1-9. Topaz cannot scratch corundum or diamond but will scratch any mineral ranked between 1 and 7.

The following table illustrates the 10 minerals and their hardness equivalents in common materials.

Important to understand is that this hardness scale isn't linear. The hardness gap between corundum and diamond differs from that between talc and gypsum. Additionally, minerals sharing the same ranking may still be capable of scratching one another.

For additional details or gemstone guidance, please contact our customer service team on 07957 371 254.