PC63 Cosmic Tea DustCOSMIC TEA DUST PC 63 Product Description PC 63 Cosmic Tea Dust is a sparkly, dark brown glaze, which breaks a light yellow brown over texture. The sparkle shifts subtly from silver to copper to give the glaze an iridescent quality. CONE 5 6 Safety Warning Tableware producers must test all finished ware to establish dinnerware status, due to possible variations in firing temperature and contamination.