5 Essential Elements For Crystal
These crystals ended up shaped above a million a long time back In the Earth's crust. They occur once the liquid while in the Earth consolidates and the temperature chills. Other crystals kind when the liquid will make its way from the clefts and dispense minerals into the clefts.③、粗抛光：是将模具压出之毛胚，以金刚石盘直接