True amber is light enough to float in salt water, if not weighed down by other substances (like silver). This quality probably helped in its discovery- inhabitants of the Baltic Sea area can still find raw amber washed up on the shore.

The most common method make amber clear is to put the material under pressure and heat in an autoclave together with nitrogen. After this procedure, it is put into an oven to obtain the sunspangles and the cognac color. This heating and treating is made to make amber jewelry more attractive

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