The Astillero Mine is a very small mine lying in the Sierra el Rosario, roughly 20 km southwest of the famous Ojuela Mine. Both are in the Municipio of Mapimí and a preponderance of specimen material from Astillero has been sold as coming from Ojuela. Astillero exploited a series of small pods of oxidized lead-zinc-silver replacement mineralization emplaced in limestones along the contact of a small stock. It is currently being explored by Grupo México.

The Astillero Mine produced a moderate number of odd light tan to off-white pseudomorphs of hydroxylapatite replacing at least three other unidentified species. Two of the species had bladed elongate habits, one with strong longitudinal striations and another had more equant rounded blades. Stibnite, hemimorphite, vivianite and gypsum have been suggested as precursors for the former and barite for the latter. Given the habits, striations and precursor mineralization, the latter three are reasonable.

What is less reasonable is the historical identification of what has been shown to be hydroxylapatite (Orligileri, written communication). Forbesite, a discredited species now known to be a mixture of cobaltian annabergite and arsenolite, is the most common misidentification with stibiconite, mimetite, and wilkeite (another discredited species now recognized as siliceous sulfatian apatite) adorning other labels. At least the latter two have apatite group structures!

Other Regions, Features and Areas containing this locality

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