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Creedita

Creedita is a mineral with formula Ca₃Al₂(SO₄)(F,OH)(SO₄)₃·2H₂O, in the Sulfatos group. This specimen comes from Mina Navidad, Mapimí, Durango, México and joined the Terrium collection in 2025.

Creedita from Mina Navidad, Mapimí, Durango, México — Terrium

Description

Complete spherical floater. Built from a radial burst of prismatic creedite crystals of intense orange colour, variably translucent to "gemmy", with very bright, lustrous faces. No points of attachment or basal breaks—pure symmetry.

About Creedita

Complex hydrated calcium–aluminium fluorosulphate. It forms in oxidised zones, almost like a "vampire" mineral, at the expense of fluorite. Acid fluids dissolve pre-existing fluorite to supply the needed fluorine, which recrystallises as these complex forms. These spheres grow "suspended" within clay pockets, allowing perfect terminations to develop in all directions without contacting anything hard.

About the locality

Mina Navidad (Rodeo, Durango) redefined the species worldwide. Although the mineral was discovered in the USA (Creede, Colorado), Mexican specimens found in the late 1970s eclipsed all earlier material for size and colour. It is an industrial fluorite mine, but it has also been worked intermittently by "gambusinos" (artisanal miners) who excavate dangerous galleries in search of these clay pockets. Production is now practically halted, making large, intact spheres very difficult to obtain.

Technical data

Catalogue No.
0133
Composition
Ca₃Al₂(SO₄)(F,OH)(SO₄)₃·2H₂O
Name
Creedita
Group
Sulfatos
Category
Asteris Explosio
Matrix
Floater
Mine
Mina Navidad
District / Municipality
Mapimí
Region
Durango
Country
México
Size (cm)
5 x 5 x 5
Weight
97 g
Acquired
2025
Etymology
Named in 1916 by Larsen and Wells for the type locality: the Creede quadrangle, Mineral County, Colorado, USA.
Quality
Top
Value trend
Al alza

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