Scratch Hardness

The scratch hardness is normally measured via Mohs test. The technique is based on the scale of hardness, called as Mohs scale, whether ten standard minerals are arranged in the order of their capability to be scratched. The softest mineral along with scratch hardness of 1 is talc while the hardest mineral, diamond, has a hardness of 10 on Mohs scale. The other type of mineral among them in increasing order of hardness are gypsum, fluorite, calcite, appetite, quartz, feldspar, topaz, corundum and sapphier. The technique of finding Mohs hardness is to compare a scratch upon the material surface, generated beneath standardized conditions through the scratch on one of the minerals taking up position from 1 to 10 on Mohs scale. Although the test had been chiefly implemented for minerals, any metal can be tested by this method. Most metals fall in mohs hardness range of 4 to 18 and it is not easy to differentiate in between two metals such hardness is close. Due to this reason this technique is not finely suited for metals.