Raw expanded vermiculite 1.Size: 0.5-1mm,1-3mm 2-4mm, ... 2.Model: 20-40mesh, 40-60mesh, 60-80mesh, 200 mesh, 325mesh Raw expanded vermiculite Vermiculite is a natural mineral that expands with ... biotite or phlogopite.Vermiculite is a hydrated magnesium aluminium silicate.Vermiculite, in its exfoliated (expanded) form, is lightweight, noncombustible, compressible, highly absorbent ...