Acrylic based glazes. There's a mix of mica and other proprietary mineral particles that refract light, like a crystal, that makes them so special.
They are an easy to use paint that creates a semi-gloss glaze that's not too shiny, not too flat, but just right. Simply brush Silks onto your project. Allow Silks to dry in between coats to keep the glaze layers distinct and create depth, or blend the colors while the glazes are still wet if you prefer that effect. They are formulated for all surfaces.