Well at long last my chagrin has ended with the purchase of a fine piece of shagreen. For those of you unfarmiliar with shagreen, it is the skin of a sting ray. Also some shark skins are called shagreen, but it usually refers to ray skins. Now shark skin, especially dogfish skin makes excellent sandpaper, but it only sands in one direction. Shagreen is different.
Traditionally sting ray skins were dyed green, hence the name, and was the traditional handle covering of swords in both the orient and in the West. What is unusual about this skin are all of those little dots, they are mineral tubercules that are very hard. When the skin is prepared the sharp edges are scraped, sanded and ground down to make them smooth.
That is why they look like shiney spots, they are an off white color and the leather is dyed black and the tubercules stay white. And they are also very hard. The reason they are used for sword handle grips is that you can hold on to the sword even if it is covered in blood or sweat or both.
Shagreen is also used to cover eating utensil handles (George Washington had a set), easy to hold in greasy fingers. Medical instruments would have handles covered with shagreen to help with the grip when things get bloody.
Aside from its colorful uses, shagreen is an excellent traditional replacement for sandpaper. (Sandpaper is early but quite expensive and not as durable.) I will be saving the center section where the big tubercules are and some other areas of different grit. I wonder how to classify the grit, spine, snoot, tail, edges. When the tubercules end the top of the ray ends and the underside is smooth and not made into leather.
The spacing of the tubercules (I like that word for some reason) varies over the surface of the skin, but the grit is determined by the user. Shagreen is the only variable grit sandpaper, now there is a novel thought. But the leather comes prepared and the mineral nodes are smooth. In order to make them more abrasive, I use a file to roughen up the surface, the finer the file the finer the grit. It is basically scratching the tubercules to get them to have sharp cutting edges which last until they mechanically wear off.
Left smooth the shagreen can be used to burnish woodwork, including turnings, similar to ‘boning’, the process of burnishing by using a piece of smooth animal bone or hardwood stick to polish the work. Shagreen is a useful material and I will make a tool handle or two, I need a piece for a friction match case to ignite the ‘lucifers’, and a goodly supply of a fine flexible abrasive.
Still searching for dogfish skin, I have had a bit of sharkskin and I did like the way it worked and it lasted for quite a while. I will be putting this stuff to the test and will talk of it later.