This item was taken from an article in the Edmonton Journal, Jan9. 1986, via the Alberta Ship Model Society Newsletter.

Sandpaper was first used in China in the 13th century when a crushed seashell mixture was stuck to parchment with natural gum adhesives. The idea showed up in Switzerland again about 200 years ago using crushed glass glued to paper. Broken glass was neither sharp enough or hard enough so the search began for a material with the hardness of diamonds. Quartz is used on flint paper; one of the least expensive around. Slightly harder and more durable is garnet paper made from red semi-precious stone.

In the late 1800's a method was " perfected whereby sand and saw dust were heated to produce silicon carbide or carborundum. A simulated sapphire, about 1/40 the hardness of diamonds can be made from aluminum oxide; the hardest commonly available abrasive. The range of hardness is reflected in the price. Sandpapers in all types conform to the same numerical system. No. 60 means that there are 60 grit particles to an inch. Thus the, smaller the number the courser the paper.

 A very fine sandpaper is made from black stone mined at Cape Emeri on the Greek island of Naxos. Sandpaper is a very precise material. AII particles in a single grade must be exactly the same size. Even one oversize particle would cause a scratch. An accordion style file is a fine way to store and your sandpaper.