How to test quartz hardness and luster?

What is quartz? Quartz is considered one of the most abundant minerals found in the Earth crust that comes second in abundance after feldspar. The term ‘Quartz’ is derived from the Polish words “Twardy” and “kwardy” meaning ‘hard’. It is...

How to test the hardness of copper

Copper plays an important role in the life of human beings. From the delivering of electricity to the supply of water, copper made all things possible. It allows the electric current to passes through it with the same voltages; it is the good conductor of electricity....
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