Pearlizers are cosmetic ingredients used to obtain luster and shimmering effects in cosmetic products. Generally, the luster effect is achieved by microfine crystalline compounds (e.g. pearlescent pigments or special chemical molecules) able the reflect light waves. Pearlizers are very often used to provide a luxurious character to a cosmetic product. Pearlizers used in personal care products as shampoos and shower gels often have also thickening and emulsifying effects.