粗あら砥と

noun

rough grindstone; coarse whetstone

A sharpening stone with a coarse grit, used for initial shaping or repairing blades.

• 刃はこぼれした包ほう丁ちょうは、まず粗あら砥とで研とぎます。

  For a chipped kitchen knife, first sharpen it with a coarse whetstone.