Grinding Pigments

grinding tools

I’ve often used home-brewed pigments for varnish colors. When they’re finished, they are clumped, and sometimes gritty, in large pieces. To put them into varnish, one first needs to grind them to a fine powder.

When I worked at Bein and Fushi there wasn’t a lot of interest in raw pigments in the art world, so we had to look around to find dry pigments and the tools for grinding them. The hardest thing to get was a muller. Mullers look like upside-down mushrooms with flat tops, and are used against a piece of ground glass to break up pigment clumps and disperse them into varnish (or oil, if you’re making oil colors). The real grinding is done with a mortar and pestle: a muller isn’t a grinding tool as much as a mixing one, to make sure that every particle of pigment gets wetted with solvent or oil. [factoid: glass mullers show up on airport x-rays as completely opaque, and when the inspectors pull them out of your luggage, they still don’t have any idea what they’re looking at, of course…  which reminds me of the time I tried to take a chinrest key into a federal courthouse.]

The first one was so hard to find, that for a while after that I went hog-wild buying them whenever I saw them. They turned out to be easier to find in England, so I came back from several trips with more of them (I was particularly pleased by the little ones with knob handles which came from a wonderful artist’s store near the British Museum in London, Cornellisen’s –if you ever go to London, put it on your list of places to visit. Unlike the US where the exterior may not be mirrored inside, the inside of Cornellisen’s is even better than the facade).

I have more than the ones in the photo. The lean one in the back is the first one. The steel “muller” is actually a meat pounder I bought in a cooking store. I haven’t ever tried it, but for $6, I couldn’t resist. The big one in the front was a going-away present from the guys in the B&F shop, and has my name, all their names, and some other things sand-blasted into it (you can read “CHICAGO MICHAEL” on the top of the handle).

Mortars and pestles, which are necessary if you’re making pigments from scratch, but not always if using commercially-made ones, are easier to find, of course, so I have a variety of sizes, and one that’s just for a single one of my home made pigments that tends to stain everything it touches.

In Renaissance art studios, grinding pigments was childs’ work, and one of the primary jobs of the very young apprentices. It doesn’t take any skill, just lots of patience and time.

Scroll to Top