bahan yang lembut
Kalsit, dolomit, Kaolin, barit, Kuarsa, Talk, Pasir Zirkon, Wollastonite, Batubara Powder, Kalsium Cahaya Karbonat, Mika, Bauksit, Attapulgite, Brucite, Bentonit, Garnet, Magnesit, Andalusite, pyrophyllite, Kalium Feldspar, Diopside, Rectorite, Diatomite , Gypsum, Pearlite dll
bahan keras
Carborundum, Boron Carbide, White Korundum, Zirconia, Cerium Oxide, Suhu Tinggi Alumina, Silikon Nitrida, Boron Nnitride, Brown Fused Alumina dll
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