I might have mentioned in a previous post that it should be possible to obtain pigment for use with egg tempera by grinding up the scrappy end pieces of pastels. After all, pastels are only raw pigment bound with gum arabic. Yesterday my wife and I made shopping trip to Ilkley where, incidentally, our nearest art materials shop is to be found. There is also a very fine household goods store. I had the idea that it might be useful to buy a pestle and mortar there and put my idea into practice. I could hardly lose given the exorbitant price of pigment.
Today I decided to try out this project, as I have begun a couple of new experiments with tempera. So I dug out a couple of boxes of pastels I’ve had for some time, in which several of the colours are now reduced to fragments which are too small to be used conveniently in the conventional way. A few minutes with the pestle and mortar had these reduced to a very convincing powder of an attractive colour, which ought to be very suitable for inclusion in what I want to do tomorrow. I’ll let you know!
Incidentally, one thing I have discovered already is that it is very important in this situation to use a proper dust mask. The powder produced by grinding is very fine, and prone to drift about in the air. I dread to think what is in some of these pigments, many of which are made from powdered rock and when you look at the chemical names of some of them they are known to be poisonous. I have heard that there are some artists using pastels who, for these reasons, actually use dust masks all the time while working.