Sericite is a silky, silvery powder which feels soft on the skin and provides an ideal base when making mineral based make up, foundation and eye shadows. Sericite is a naturally occurring, uncoloured mineral which can be used as a filler and bulking agent, assists adhesion in some formulas in combination with Iron Oxides.
The name comes from the Latin sericus, meaning "silken" in reference to the location from which silk was first utilized, which in turn refers to the silky sheen of rocks with abundant sericite. (ref Wiki)
If you are beginning to experiment with Mineral Makeup, Bramble Berry’s Mineral Makeup Booklet will provide you with basic information and loads of formulas.
The above graphic is the same as Pureglow Mica, which this product will eventually replace. They are very, very similar to look at.