-- Anglesite (Pb(S[0.sub.4])) 3.1 -- Sphalerite (ZnO) -- <1.0 pyrrhotite ([Fe.sub.0.95] -- 1.4 [S.sub.1.05]) Spinel ([Mg.sub.1.01] -- 1.9 [Fe.sub.0.95][Al.sub..22] [0.sub.4]) Melanterite
((Fe, Cu, Zn) -- 1.9 S[0.sub.4] x 7[H.sub.2]0) Zincocopiapite (Zn[Fe.sub.4] -- N.Q.
White epsomite fibers occur on melanterite and chalcanthite stalactites.
Green melanterite stalactites are common throughout the mine, and rarely melanterite occurs as crystals to 2 cm.
Associated minerals are: coskreaite-(Ce), levinsonite-(Y), melanterite
, halotrichite, picketingite, apjohnite, epsomite and other hydrated sulfates.
The three species are virtually indistinguishable and occur together as dull, beige, yellow and yellowish white, powdery efflorescences and crusts associated with epsomite, melanterite
Species confirmed by X-ray diffraction during this study include alstonite, anglesite, ankerite, aragonite, barytocalcite, barite, brochantite, epsomite, harmotome, hydromagnesite, jarosite, marcasite, melanterite
, millerite, serpierite, siderite, sulfur and witherite.
Alum Cave Bluff, a Dana locality for apjohnite, epsomite, melanterite
and potash alum, has yielded good microcrystals of several rare sulfate minerals, including three new rare-earth sulfates, and is the first North American occurrence of slavikite.
Long, deep blue stalactites in the mine workings are referred to by the miners as "chalcanthite" but in fact usually prove to be cuprian melanterite
Eight entries in his Catalogue of Minerals Found in Colorado are: cuprite, fluorite, jamesonite, melanterite
, rhodochrosite, tetrahedrite, tennantite and zinkenite.
(?) [Fe.sup.2+]S[O.sub.4][multiplied by]7[H.sub.2]O
FeS[O.sub.4][center dot]7[H.sub.2]O and Chalcanthite CuS[O.sub.4][center dot]5[H.sub.2]O
Typical minerals formed under these conditions are water-soluble sulfates such as chalcanthite, melanterite
and halotrichite, along with other more insoluble minerals such as malachite and chrysocolla.