Henderson Mine, Colorado, USA

This belongs to the Climax-type class of porphyry molybdenite deposits. The Henderson orebody is associated with the Henderson granite and Primos and Urad porphyries. A central potassic zone carries a major silicified zone and the orebody is coincident with both of these. Quartz-topaz, phyllic, argillic and propylitic zones lie at progressive distances from the central potassic zone.

Major Minerals:

Molybdenite, pyrite, magnetite

Minor Minerals:

Haematite, sphalerite, galena, hubnerite

Trace Minerals:

Include ilmenorutile, columbite, uraninite, uranothorite, brannerite, xenotime, monazite, zircon (within the associated igneous rocks)


Molybdenite occurs in thin quartz veins where it lies along the vein walls or within the vein as discrete laths, polycrystalline clots or rosette-shaped aggregates. Magnetite associated with minor haematite occurs in quartz veins and is rimmed and cross-cut by pyrite. Hubnerite occurs with pyrite and topaz in quartz veinlets. Pods of molybdenite, magnetite, pyrite, topaz and muscovite are present


Wallace et al., 1978