And as usual, the PR was so generic, so ambiguous about the "mine" that it cannot even be researched. The region of Puebla? They couldn't have picked a Mexican state with less in the way of gold mining. I can't find any evidence of active gold mining or exploration going on in the State of Puebla.
The State of Puebla is not known for precious metal mining, however, they do produce some calcite, marble, calcium oxide, onyx, and lime. There has been some sporadic exploration for gold in Puebla, but no active mines that I can determine.