J archived mineral specimens

Jarosite

#41306

Availability: Sold

Locality: Sequoia Pit, Lone Tree mine, Humboldt Co., Nevada, United States
Formula: KFe³⁺₃(SO₄)₂(OH)₆
Size: SmCabinet 5.5x4.5x2cm

Beautiful amber tabular crystals on Jarosite, less than 1mm, in clusters within large vug.

Jarosite at Dakota Matrix Jarosite at WebMineral Jarosite at MinDat

Jeanbandyite

#BAC60666

Availability: Sold

Locality: Mt. Pleasant mine, Charlotte Co., New Brunswick, Canada
Formula: (Fe³⁺,Mn²⁺)Sn⁴⁺(OH,O)₆
Size: Thumbnail 3x2.4x2cm
Tagged: tin

Murky yellow, crude tetragonal dipyramids to about 0.5mm. There are numerous crystals all over the specimen. I am not sure what the brownish yellow spherical groups are. The matrix is Fluorite.

Jeanbandyite at Dakota Matrix Jeanbandyite at WebMineral Jeanbandyite at MinDat

Jennite

#AK44327

Availability: Sold

Locality: Crestmore, Riverside Co., California, United States
Formula: Ca₉Si₆O₁₆(OH)₁₀·6H₂O
Size: SmCabinet 6.5x4x1cm
Special Info: Type Locality

I have dealt a lot of Crestmore material and acquired quite a bit over the years, but I have never seen a Jennite of this magnitude from the type locality, Crestmore. All of the white crystals on this specimen are Jennite. On the back of the old label Kidwell states whee his specimen originated: "1963 C.M. Jenni".....a bonus of course.

Jennite at Dakota Matrix Jennite at WebMineral Jennite at MinDat

Jensenite

#42307

Availability: Sold

Locality: Centennial Eureka mine, Tintic dist., Juab Co., Utah, United States
Formula: Cu²⁺₃Te⁶⁺O₆·2H₂O
Size: Thumbnail 2x1.5x0.4cm
Tagged: copper , tellurium

Small, tiny, about 0.25mm or less single bright green, extremely rare, Jensenite crystal associated with dark, grass green, Mcalpineite on the backside. The Jensenite was visually identified by Martin Jensen himself.

Jensenite at WebMineral Jensenite at MinDat

Jensenite

#65489

Availability: Sold

Locality: Centennial Eureka mine, Tintic dist., Juab Co., Utah, United States
Formula: Cu²⁺₃Te⁶⁺O₆·2H₂O
Size: Thumbnail 1.8x1.5x0.6cm
Tagged: copper , tellurium
Special Info: Type Locality
Special Info: EDS Confirmed

Tiny 0.3mm emerald green cubic-looking (it is monoclinic and usually prismatic) crystal at the arrow. Comes with Martin Jensen's hand-written label. Very rare.

Jensenite at WebMineral Jensenite at MinDat