Sandpaper Only Works If It Is Rubbing Against Something
Feld Thoughts
MARCH 25, 2018
Shark skin (placoid scales) has also been used as an abrasive and the rough scales of the living fossil, Coelacanth are used for the same purpose by the natives of Comoros. From Wikipedia: “The first recorded instance of sandpaper was in 1st-century China when crushed shells, seeds, and sand were bonded to parchment using natural gum.
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