Zacatecas
Concepción del Oro
Concepción del Oro is a mining town, 260 kilometres north-east of Zacatecas.
Concepción del Oro $1
A silver one peso coin, one of the rarest revolutionary pieces, is known to have been minted here. This coin’s authencity has been questioned, as to whether it is really a coin of the time or is a piece invented years later.
There is an example in the Banco de México collection and in the mid-1970s another piece appeared in Monterrey, Nuevo León. which was found in a batch of revolutionary 2 pesos Guerrero coins. Recently it is said that a person from Puerto Isabel, Texas acquired 22 copies from a Mexican who said he dug them up in Matamoros, Tamaulipas, but this version is not confirmed.
(from Carlos Abel Amaya Guerra, Compendio de la Moneda de la Revolución Mexicana)