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> (Note: Emery is a granular rock composed mainly of corundum—a crystalline compound of silicon and carbon—magnetite and spinel. Here, `emery’ and `corundum’ a

> (Note: Emery is a granular rock composed mainly of corundum—a crystalline compound of silicon and carbon—magnetite and spinel. Here, `emery’ and `corundum’ are used for the abrasive powders derived from these rocks.) Corundum is Aluminium Oxide (not clear if this is part of the original article?)

CapitalistCartr 2y ago
Yeah, carborundum is the correct word.
- oersted 2y ago
  Reminded me of the witty: > Illegitimi non carborundum
- kragen 2y ago
  emery is corundum (sapphire, aluminum oxide, α-alumina) and carborundum is silicon carbide (a compound of silicon and carbon)

> (Note: Emery is a granular rock composed mainly of corun­dum—a crystalline compound of silicon and carbon—magnetite and spinel. Here, `emery’ and `corundum’ a

> (Note: Emery is a granular rock composed mainly of corun­dum—a crystalline compound of silicon and carbon—magnetite and spinel. Here, `emery’ and `corundum’ a

> (Note: Emery is a granular rock composed mainly of corundum—a crystalline compound of silicon and carbon—magnetite and spinel. Here, `emery’ and `corundum’ a

> (Note: Emery is a granular rock composed mainly of corundum—a crystalline compound of silicon and carbon—magnetite and spinel. Here, `emery’ and `corundum’ a