Calcium carbonate: 82% ~ 90%
Shell: 10% ~ 16%
Moisture: 2% ~ 4%
In addition to calcium carbonate, there are a small amount of calcium oxide, calcium phosphate and silicon oxide in inorganic substances. Keratin contains nearly 20 kinds of amino acids.
In addition, pearls also contain metal elements such as magnesium, manganese, aluminum, copper, iron, sodium, zinc, silicon, titanium and strontium. These metal elements play an important role in the formation of pearl color. For example, gold, yellow and cream pearls contain a lot of copper and silver; Fleshy and pink pearls contain more sodium and zinc. The keratin contained in it is the general name of the organic matter contained, and it has strong resistance to chemical reagents. It is not decomposed by inorganic acids at low temperature, and neither stomach nor pancreas can digest it.