C archived mineral specimens

Calciojohillerite

#52390

Availability: Sold

Locality: Tolbachik Volcano, Kamchatka, Russia
Formula: NaCaMg₃(AsO₄)₃
Size: Miniature 3.5x3.5x2cm
Tagged: arsenate
Special Info: XRD Confirmed
Special Info: EDS Confirmed
Special Info: Type & Only Locality
Special Info: Author's Material

Calciojohillerite is a greenish to yellowish, blue to almost colorless well-shaped, terminated crystals (about 1 mm) combined in clusters / crusts on basalt scoria altered by fumarolic gas. The specimen is very rich. It is one of the few study specimens from Igor Pekov's collection used to characterize the new mineral.

A more detailed locality is: Arsenatnaya fumarole, Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka, Russia.

Calciojohillerite at Dakota Matrix Calciojohillerite at WebMineral Calciojohillerite at MinDat

Calciomurmanite

#48314

Availability: Sold

Locality: Mt. Pyalkimpor, Lovozero Massif, Kola Peninsula, Russia
Formula: (Na,☐)₂Ca(Ti,Mg,Nb)₄[Si₂O₇]₂O₂(OH,O)₂(H₂O)₄
Size: Miniature 4x2.5x2cm
Special Info: Type Locality
Special Info: XRD Confirmed
Special Info: EDS Confirmed
Special Info: Author's Material

Calciomurmanite is Na-Ca ordered analogue of murmanite. Murmanite does not contain calcium, only Na, by strict definition. Otherwise, you cannot tell these two minerals apart visually. Calciomurmanite crystals occur as thin plates and somewhat micaceous. The cleavage surfaces have a mother of pearl luster. This specimen was verified by Dr. Igor Pekov and was part of his study to define the mineral for publication. It is an approved IMA mineral, although not yet published.

Calciomurmanite at Dakota Matrix Calciomurmanite at WebMineral Calciomurmanite at MinDat

Calcite

#48406

Availability: Sold

Locality: Kambove dist., Katanga, Democratic Republic of Congo
Formula: CaCO₃
Size: SmCabinet 6x5.5x2.5cm
Tagged: carbonate

Magenta rhombic crystals from 1-5mm. Brilliant color and beautiful specimen.

Calcite at Dakota Matrix Calcite at WebMineral Calcite at MinDat

Calcite

#48513

Availability: Sold

Locality: Shigar Valley, Baltistan, Northern Areas, Pakistan
Formula: CaCO₃
Size: Cabinet 11x6x7cm
Tagged: carbonate

Calcite, especially this size, is rare in pegmatites. Most carbonates are associated with the primary phosphates. This specimen is an unusually large Calcite crystal perched nicely on Microcline. The specimen was photographed for figue 4-24 in London's "Pegmatites" book. See prov. tab for London't label.

Calcite at Dakota Matrix Calcite at WebMineral Calcite at MinDat

Calcite

#RW48772

Availability: Sold

Featured: Featured in Special Editions
Locality: Blackstone mine, Shullsburg, Lafayette Co., Wisconsin, United States
Formula: CaCO₃
Size: Cabinet 9.5x5.5x2.5cm
Tagged: carbonate

An excellent specimen with good provenance. The specimen was personally collected by RJ Waidler in 1968 from underground at the Blackstone mine. The Calcite crystals are of rhombic forms with a cool frosted, faint yellow color. The crystals average about 8mm. The matrix is massive, crystalline dark reddish brown Sphalerite.

Calcite at Dakota Matrix Calcite at WebMineral Calcite at MinDat