Pearlescent pigments natural pearl essence

Although pearlescent pigments encompass the natural pearl essence derived from the fish and also the various crystal forms of bismuth oxychloride, it is the coatings of titanium dioxide and iron oxide on mica that have gained the most acceptance and are the most commercially successful. It is the coatings of titanium dioxide on mica and their derivatives that are the subjects of this study. 

The original pearlescent colorant was natural pearl essence (natural fish scales). The material is too fragile for most plastics processing, but it has been used in cellulose acetate eyeglass frames. Synthetic pigments include basic lead carbonate, lead... 

Natural pearl essence is very expensive but shows some advantages over synthetic pearlescent pigments. For example, it shows a high but soft luster (no = 1.79 (parallel) to 1.91 (perpendicular)), It is not brittle and has a relatively low density of 1.6 g/ cm, which reduces settling in liquid formulations. It is almost exclusively used in expensive cosmetic applications. 

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