I came across some calceteiros in the process of creating the gorgeous Portuguese mosaic sidewalks.

In time, shoes polish the mosaics to a slippery shine.

In Lisbon, a Carpet of Stone Beneath Their Feet is an excellent article on how calçada (patterned pavements) are made, the history of the mosaic pavements, and Escolas de Jardinagem e Calceteiros, a City school where this unique stone paving is taught. Highly recommended, if you enjoyed my little article.