The Mohs Hardness Scale is a standard that indicates the hardness of minerals. It was first proposed by German mineralogist Frederich Mohs in 1822.
Mohs HardnessTypical Material 1 Talc 2 Gypsum, Rock salt 2.5 Fingernail, pure gold, silver, aluminum 3 Calcspar (calcite), copper coin (penny) 4 Fluorspar (fluorite) 4.5 Platinum, iron 5 Apatite 6 Felspar, orthoclase, titanium, spectrolite 6.5 Steelfile, iron pyrite, glass, vitreous pure sil...
This is evidence of the hardness of sapphire and a testament to its place at number 9 on the Mohs hardness scale. More germane to this discussion of gemstone hardness though, is the reason why sapphire and ruby (of the same family, Corundum) are so highly recommended for everyday wear je...
Mohs hardness, rough measure of the resistance of a smooth surface to scratching or abrasion, expressed in terms of a scale devised (1812) by the German mineralogist Friedrich Mohs. The Mohs hardness of a mineral is determined by observing whether its surface is scratched by a substance of kno...
3. Mostsulfidesare relatively soft (H < 5), withmarcasiteandpyritebeing examples of exceptions (H < 6 to 6.5). 4. Most anhydrousoxidesandsilicatesare hard (H > 5.5). Because hardness is a highly diagnostic property in mineral identification, most determinative tables use relative hardness as ...