Guampas/Mates/Cuias are a kind of glass that can be made from animal horns, usually made from cattle horns, but some people made guampas from stainless steel, wood, mate/porongo (a kind of cucurbit native from South America), or silver. The new guampa/mate/cuia or the one not used for some time needs to be watered before use, because the lower part of the cuia is usually capped with a round piece of wood. By filling the guampa/cuia with water the wood expands, covering all leaks in the guampa/cuia. Guampas, mates and Cuias are also made from wood and covered in leather or steel.