3 января, 2016 
Pokraskin The first commercially successful synthetic pearl luster pigments were hexagonal lead salt crystals, especially basic lead carbonate Pb(OH)2 • 2 PbCO3. Basic lead carbonate is precipitated from aqueous lead acetate with carbon dioxide under carefully
controlled reaction conditions.
3 Pb(CH3COO)2 + 2 CO2 + 4 H2O ^Pb(OH)2 -2 PbCO3 + 6 CH3COOH
The resulting platelets are less than 0.05 pm thick and show hexagonal dimensions of about 20 pm, yielding an aspect ratio of >200. Because of their high refractive index of 2.0 and their even surface, they exhibit a very strong luster. If the thickness of the platelets is increased by slightly modified reaction conditions, interference colors can be obtained [5.122, 5.123, 5.128, 5.130].
The crystals are very fragile and are handled only in dispersions. They settle very fast because of their density of 6.14 g cm-3. The use of basic lead carbonate is also limited by its low chemical stability, the toxicity of its by-products, and toxicological concerns in its application areas.
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