Mica Powder: Mica Powders are particles coated with titanium dioxide and/or iron oxide. They are environmentally safe, non-toxic, non-tarnishing and universal. Mica powders can be added to varnishes, shellacs, acrylics for painting and glazing. Mica powder can also be flash gilded directly on a sized surface. Mica colors can be intermixed with each other to create additional colors. The density of coverage depends on the amount of powder used. Final effect can be altered by varying the color underneath. Mica powders withstand firing temperatures up to 900 degrees Celsius (1,652 degrees Fahrenheit). All mica powders are for interior use.