Mineralization in the Sierra Madre Mountains of West Central Mexico consists mainly of subvertical silver-gold veins cutting a flat lying felsic-mafic volcanic sequence. The Dolores deposit of Minefinders and the Ocampo deposit of Gammon Lake share many characteristics with the Santa Cruz Property, but the host rocks at Santa Cruz are limestones and conglomerates, not the andesitic and felsic volcanic rocks prevalent at the other deposits. At Delores, the veins are near feeder dikes and plugs, which are part of a major volcanic centre. Similar volcanic centres have not been identified near the Santa Cruz mineralization, but may be found by more detailed investigations as volcanic rocks dominate the regional geology. Near the Yesos adit the host rocks are moderately dipping white bedded limestones. Elsewhere the host rocks have been described as grey to dark grey limestones. According to the Mexican Government Geological Survey (CRM) the lower westerly adits lie within a conglomerate. The contact with the overlying limestone seems to dip moderately southeasterly at about 20 degrees.

Attitudes of the Yesos or Santa Cruz vein shows that it strikes northwest-southeast and dips from 45 to 65 degrees southwesterly. The vein was investigated on surface and four levels by adits; it seems to be continuous for 1500 metres. Adits have probed it from the northwest and southeast. Some of these are accessible. Old pits and adits suggest at least four parallel veins are present. Of these, El Salon and its associated veins lie some 650 metres to the northeast and seem to form a parallel system. Similarly La Pieta Vein and an associated vein were investigated 350 metres to the southwest. In the southern part of the property other veins such as the El Puerto, La Consentida, La Correlitos, Santa Rita, El Puerto and Sin Nombre have been traced on the CRM map; very little is known of their extent or mining history. Only the Correlitos was visited, and its mine openings suggest a much more significant mining history than indicated from existing maps.