These are a collection of ground earth paints. The old masters used them. A lot of them died prematurely because of lead poisoning.
We got them from an artist friend of Warwick’s 20 years ago, when he died. For a while they took up space but were mostly unused
I have experimented with these and intend to do some work with them. I have tried water colour, by mixing them with gum arabic and oil colour with linseed oil and turpentine or liquin, also mixed egg tempora and acrylic by mixing it with PVA glue. I even added fabric fixitive to my created acrylic and painting it on fabric.
Yes, to do this, do the art work outdoors, well ventilated and with gloves and face mask. That way you stay safe. I doubt if anyone wants them, they buy the paints and don’t bother with this type of work. However, I think experimentation is fun as long as you are careful