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Occurs in Pinal County.

Chemical Formula: PbSiO3

Specific Gravity: 5.6-6

Luster: Vitreous to adamantine

Hardness: 4-5

Alamosite is a lead silicate mineral that typically forms translucent, colorless to white crystals. It is named after Alamos, Sonora, Mexico, where it was first discovered.

Next Pinal County mineral: Albite

MinDate Alamosite

Alamosite’s is a mineral that falls within the category of sulfates. Its chemical composition is typically hydrated aluminum sulfate. This mineral is often encountered in the form of white, chalky aggregates or fine powders.

The name “alamosite” originates from Alamosa Creek, New Mexico, where the mineral was first identified. It is frequently found in association with other sulfates and secondary minerals, often forming due to the weathering and alteration of primary aluminum-rich minerals in sulfide ore deposits.

Alamosite is of interest primarily to mineralogists and researchers studying the alteration processes that occur in mineral deposits over time. It is not a commonly recognized mineral outside of geological and mineralogical circles due to its relatively limited occurrence and lack of commercial significance.