Compañía Española de Minas de Río Tinto
Compañía Española de Minas de Río Tinto (CEMRT) was a Spanish company that operated between 1954 and 1970, mainly in the province of Huelva. Dedicated to mining activities in the Rio Tinto-Nerva basin, over the years the company diversified its business into other sectors.
Source: Wikipedia — Compañía Española de Minas de Río Tinto (CC BY-SA 4.0)