Recent content by nbadream178

Drop small concentration HCL on the surface of the pearl and then swipe the test strips over the area

I know that the concentration of Manganese in freshwater pearls is much higher than in saltwater pearl. But I want to know the reason of these concentration difference. Also, Can we use manganese test strip to distinguish the saltwater and freshwater pearl? Because there is Manganese...

I know that moh's hardness of cultured pearl is 2.5-4.5 How about the hardness of different type of imitation pearl(plastic and glass)? I want to distinguish the imitation pearl by moh's hardness test.