1. I-brown corundum abrasive, equlunqwe ngokukodwa i-Al2O3, inobunzima obuphakathi, ubunzima obukhulu, amasuntswana abukhali kunye nexabiso eliphantsi, kwaye ifanelekile ukucubungula isinyithi esinamandla aphezulu.Zombini i-microcrystalline corundum abrasive kunye ne-black corundum abrasive ziphuma kuyo.White corundum Whit...
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