Specification. Particle size, packaging & deliveries: Potash feldspar powders are available in 100,150,200,250,325 etc meshes & in .20 and 10 um particles. Potassium Feldspar is packed in new/used HDPE/PP laminated / unlaminated 50 kg bags. (For exports, packaging in 50kg, 1000kg, 1250kg, 1400kg laminated bags duly palletized, shrink wrapped is …