Qhov ceev: 1.2-1.8 (vim qhov sib txawv nyob ntawm hom thiab xim)
Particle loj faib: nruab nrab particle loj 32-40 μm, nrog μm hais muaj ntau tshaj 99% ntawm tag nrho.
Txheej cov khoom muaj xws li gloss (2% -100%), cuam tshuam tsis kam (Ntau dua lossis sib npaug li 1 kg * 50 cm), yoog raws (khoov Tsawg dua lossis sib npaug li 2 hli, cupping Ntau dua lossis sib npaug li 7 hli), adhesion (Qib 0), hardness (Ntau dua lossis sib npaug rau H), tshuaj tiv thaiv (tiv taus rau 55% sulfuric acid, hydroxide thiab resistant 55% sulfuric acid.