Chalky

Troll potter based in Ankh-Morpork.

In Jingo his sand heap provides the material (traces of feline incontinence included) for the ordnance map of Klatch in the Rats Chamber.

During Feet of Clay his stores were robbed for clay. He didn't report the robbery at first, because "Wasps don't complain much when they get stung."

It's possible he is a member of the Breccia, since he was a maker of conveniently hollow statues that hid Slab.