These extra-fine watercolors span the color spectrum from the historical to natural earth and quinacridones. Outstanding color strength, extremely vibrant colors and excellent brushing properties make these paints desirable for any watercolor artist. The pigments are procured from every continent except Antarctica, and the paints are manufactured in Seattle, Washington.PrimaTek Watercolors are made from naturally occuring pigments, reviving the tradition of making paints the way the Egyptians and other cultures did but with modern technology. Sourced by geologists, these unique pigments have amazing and interesting granulating properties. The luminescent watercolors add a touch of special color found in nature that regular colors cannot match. They're made from mica pigment, thin transparent particles coated with highly reflective metal oxides. They show best as glazes over darker colors and are excellent mixed with other colors adding a bit of their luminescent glow. The duochrome colors contain one pigment that bounces between two colors causing a color shift. Interference pigments display a subtle sheen and they cause refraction where a particle of light enters the paint/pigment matrix and scatters light. Iridescent colors reflect light and their semi-transparent quality adds a fascinating sense of depth to artwork. Pearlescent colors add opalescence - like an opal or pearl - to the color it's mixed or glazed with.