Bismuth Oxychloride (CI 77163)

Bismuth oxychloride (CI 77163) is a white solid pigment that has been used for many years as a colorant. This ingredient is sometimes known as pearl white due to its lustrous, pearlescent appearance.

Its appearance is a result of light reflecting and refracting through the layers it forms. These layers are molecular sheets that consist of individual planes of either bismuth, chloride, or oxygen ions that alternate in specific order.

In nature, this ingredient exists as a mineral known as bismoclite, a rare member of the matlockite group of minerals. It can be found naturally in parts of Australia and South Africa, but it is synthetically produced for commercial purposes. Synthetic production of this compound involves the reaction of bismuth chloride with water through hydrolysis.

Bismuth oxychloride (CI 77163) can be found in all types of skincare products, from lotions and creams to all types of color cosmetics, including pressed powders where it is often used as a talc alternative. It is insoluble in both water and oil, but it can be dispersed into each as-is or by using surface modifications.

Some research suggests that the crystalline structure of bismuth oxychloride can cause skin reactions or sites of irritation when applied. However, more studies must be performed in order to validate this claim.