El Boleo

El Boleo is a copper-cobalt-zinc-manganese deposit located adjacent to the port city of Santa Rosalía, Baja California Sur in Mexico.

[1] The discovery of the copper ore in the region is historically credited to a rancher named José Rosas Villavicencio in 1868.

El Boleo was first operated, on a large commercial scale, in 1885 by the French company Compagnie du Boleo which obtained control of the property and began mining, after receiving an extensive concession and 70-year tax exemption granted by Mexican president Porfirio Diaz.

As the ore was extremely rich, (apparently a complex mixture of oxides and sulfides of up to 15% Cu) it could be fed directly to the smelter without pre-processing other than crushing.

The Greek doctor Diamant Hadji-Mihaloglou was briefly in charge of the medical services at the hospital; he then returned to France.

Subsequent exploration established that vast amounts of copper ore, as well as commercial quantities of cobalt, zinc, and manganese still existed on the site.

The DFS was completed in 2007 by the current lease holder - Minera y Metallurgica del Boleo - and followed by a Technical Report update issued in March 2010.

Small scale testing has established that a hydrometallurgical process can effectively recover all four metals, with competitive economics.

An agreement was reached in July 2012, transferring majority ownership interest and control of the project to the Korean consortium, in return for funding the reported cost overruns.

[4] In January 2015, production started in El Boleo, after the Canadian Baja Mining Corp fought hard to find investors to keep the project running.

[6] The ore (mineralization) occurs in a strata bound form known as mantos in El Boleo Formation which is a range of clastic sedimentary rocks from siltstone to sandstones, with some claystone.