Spanish to English Other Art, Arts & Crafts, Painting jewelry making

This is a biography of a Ecuadorian jewelry maker. The context is:
"Los materiales que utilizo para mi trabajo como piedra, alpaca y alambre los consigo de comerciantes que traen del Peru, los CASCAJOS y canutillos los consigo en los almacenes de la zona."

I'm not sure if STONES would be accurate enough for this context. I keep seeing translations like RUBBLE and GRIT, but of course that's not going to work for this sentence.

Thanks for your help!