Dmitry Stepanenko's Photo Gallery

K3V-JADAndradite (Var: Rainbow Garnet) Ca₃Fe³⁺₂(SiO₄)₃

Rainbow Garnet prospects, Arlit, Agadez, Niger

Largest Crystal Size: 11 mm

Rainbow garnet from new find made in Niger in January 2019. Gemological properties (SG = 3.89, RI > 1.79) correspond to nearly pure andradite (similar to Japanese rainbow garnets). Analyzed using EDS: as it was expected from gemological properties, the sample is nearly pure andradite with minor spessartine and grossular constituents. Obtained from Sylvain Leroux.

5Q3-4AAQuartz (Var: Amethyst) SiO₂ , Calcite CaCO₃

Rivne Oblast, Ukraine

Field of View: 14 mm

Amethyst and yellow calcite "flowers" in basalt geode. Faces of amethyst crystals display iridescent colors similar to so-called "iris quartz" found, for example, in India. Several shots with different angles of illumination were stacked together using CombineZP software to display as many iridescent faces as possible in one image. Real colors are less saturated. Child photo shows general view of the sample.
Dmitry Stepanenko collection and photo. Gift of Anton Sitnikov, Ukraine; self-collected by Anton.

WKL-WX5Quartz (Var: Amethyst) SiO₂

Bill's Old Amethyst Mine, Pearl Station area, Thunder Bay District, Ontario, Canada

Dimensions: 27 mm x 25 mm x 9 mm

Polished thick section of amethyst crystal with trapiche-like pattern, inclusions of red hematite and black hematite phantom, transmitted light. Both sides of the section are shown. Child photos show color zoning in one of the arms of trapiche-like pattern and another section cut from the same crystal in transmitted and reflected light.
Dmitry Stepanenko collection and photo. Gift of John Truax, USA.

1AQ-GDCCorundum (Var: Sapphire) Al₂O₃

Ratnapura District, Sabaragamuwa Province, Sri Lanka

Dimensions: 15 mm x 12 mm x 8 mm

Crystal of blue sapphire with trapiche pattern (fixed 6-ray star). Trapiche pattern in sapphires is caused by phlogopite inclusions (Gems & Gemology. Winter 1996. P. 249). Rays of the "star" are oriented perpendicular to the prism faces of the crystal. Close-up photo shows fine color zoning parallel to the prism faces.
Dmitry Stepanenko collection and photo.

34M-38JQuartz SiO₂

Ouray Mining District, Ouray County, Colorado, USA

Pseudomorph of quartz after calcite. Transmitted light demonstrates that sample has thin shell-like structure. View from the back shows imprints of calcite crystals.
Maximum dimension of the sample is about 50 mm.
Dmitry Stepanenko collection and photo.

V7W-7NVApophyllite Group AB₄[Si₈O₂₂]X · 8H₂O , Stilbite Subgroup M_6-7[Al_8-9Si_27-28O₇₂]·nH₂O , Heulandite Subgroup (Na/Ca/K)_5-6[Al_8-9 Si_27-28 O₇₂]· nH₂O

Jalgaon District, Nashik Division, Maharashtra, India

Green crystals of apophyllite and colorless bladed crystals of stilbite are growing on pseudomorph of several minerals after calcite. Two large finger-like pseudomorphs are clearly visible and perfectly preserve shape of original crystals. Calcite crystals are now dissolved and pseudomorphs have empty spaces inside them (see photo from the bottom). View from the bottom also shows trigonal sections of pseudomorphs and complex layered structure of their walls: they consist of several alternating layers of different minerals. According to the references http://www.johnbetts-fineminerals.com/jhbnyc/mineralmuseum/picshow.php?id=29038, http://www.johnbetts-fineminerals.com/jhbnyc/mineralmuseum/picshow.php?id=29039 outer layer of pseudomorphs consists of heulandite microcrystals.
Maximum dimension of the sample is about 85 mm.
Dmitry Stepanenko collection and photo.

EHR-X40Wavellite Al₃(PO₄)₂(OH,F)₃·5H₂O

Apricke quarry, Hemer, Märkischer Kreis, Arnsberg, North Rhine-Westphalia, Germany

This sample is probably a pseudomorph of wavellite after calcite. Crystals of calcite overgrown with wavellite were dissolved leaving hollow casts. Rhombic sections of calcite crystals are still clearly visible. Under magnification wavellite exhibits typical banded appearance.
Maximum dimension of the sample is about 40 mm.
Dmitry Stepanenko collection and photo.

TWP-MDWCalcite CaCO₃ , Quartz SiO₂

Bleiwäsche quarry, Bleiwäsche, Bad Wünnenberg, Paderborn, Detmold, North Rhine-Westphalia, Germany

Large crystals of calcite are overgrown with sparkly microcrystals of quartz. View from the bottom shows rhombic sections of calcite crystals overgrown with thick layer of quartz.
Maximum dimension of the sample is about 60 mm.
Dmitry Stepanenko collection and photo.

UMX-UW6Vivianite Fe²⁺Fe²⁺₂(PO₄)₂·8H₂O , Siderite FeCO₃

Huanuni mine, Huanuni, Pantaleón Dalence Province, Oruro, Bolivia

Dimensions: 60 mm x 40 mm x 20 mm

Blue-green iridescent crystal of vivianite is sitting on matrix coated with brownish microcrystals of siderite (visual identification, see microphotograph).
Dimensions of the sample are about 60 x 40 x 20 mm.
Dmitry Stepanenko collection and photo.

4JM-8RMRhodochrosite MnCO₃ , Baryte BaSO₄

Quarry E, Kamysh-Burun Trough, Kerchenskoe deposit, Kerchenskyi (Fe)-ore basin, Kerch Peninsula, Crimea, Ukraine

Pseudomorph of rhodochrosite after bivalve shell. In transmitted light it is seen that shell is completely replaced with rhodochrosite. Early Pliocene, Kimmerian stage, 5.2-3.4 Mya. Inside shell there are crystals of baryte.
Maximum dimension of the shell is about 30 mm.
Dmitry Stepanenko collection and photo.