Opal: Opal has been a mystery for centuries. No two opals look alike. The word “opal” was derived from a Greek word opallos, meaning ‘to see changes of color’. Opal is derived as a precious gemstone which is formed from non-crystalline silica gel. It consists of 6 to 10 per cent water and small silica…
Gold mining consists of the processes and techniques employed in the removal of gold from the ground. Earlier gold was mined using different methods like Panning, cradling, dry blowing, shaft mining, Puddling and dredging. Nowadays open cut mining and underground methods are used for gold mining. Panning is one of the oldest techniques of separating…