Tsakhirin Khuduk Y-Zr-Nb deposit, Khaldzan Buragtag massif, Myangad District, Khovd Province, Mongolia

3 mm group of Hinnganite-(Ce) dipyramidal crystals, etched from filled with Calcite cavity in Epidote-Quartz metasomatites, formed by replacement of rare metal alcaline granitic pegmatite. Such Hingganite is Fe-free and enriched with Nd up to formation of zones of Nd-dominant Hingganite-(Nd). Mineral is covered by yellow spherulitic ...

© Pavel M. Kartashov collection & photo

Pink triangular tabular crystals of aluminocerite (IMA2007-060) into cavities of black niobian chevkinite large crystal. FOV ~4x3 mm. Selfcollected in the trench #2 of Western ore zone of the deposit in July 1990. Pavel M. Kartashov collection and photo.

© Pavel M. Kartashov collection & photo

Termination of large broken Chevkinite-(Ce) crystal from rare-metal alkaline pegmatite. Surface of the crystal (the right part of the picture) is altered and overgrown by later brown astrophyllite-like allanite-(Ce), pink crystals of IMA2007-060 (aluminoan cerite), and microscopic hingganites-(Ce) and -(Nd) (unvisible according to their small ...

© Pavel M. Kartashov collection & photo

glassy brown fergusonite-(Y) with zonated piramydal crystals of fergusonite-(Y)/fergusonite-(Nd) with overgrown spherulite (red arrowed) of very light pinkish (dychroic) hingganite-(Nd) In Coll. M. Slama (collected and confirmed by Pavel Kartashov) Canon EOS 250D with noname 10x chinese Objective, stacked from 95 Images using Zerene Stacker ...

Large black laths of aenigmatite (some of them are up to 10 cm long) into nordmarkit-pegmatite from the northern slope of Ulyn Khuren Mt. Exactly this specimen wasn't investigated, but some crystals of this primary aenigmatite were decay into mixture of wilkinsonite, magnetite, ilmenite, two unidentified (new?) alkaline Fe-silicates and ...

© Pavel M. Kartashov collection & photo

Cross section of the large Fergusonite-(Y) spherulitic crystaline cluster. Mineral is completely metamict, so we see glassy conchoidal surface. This fergusonite is extremely enriched with Nd and contains zones and spots of Fergusonite-(Nd). Associated minerals are Quartz, Epidote, Allanite-(Ce) and Zircon. Specimen size is 4x4x1.5 cm and its ...

© Pavel M. Kartashov collection & photo

Large black laths of aenigmatite into nordmarkit-pegmatite from the northern slope of Ulyn Khuren Mt. Under microscope is visible, that primary aenigmatite of these large crystals was decay into mixture of wilkinsonite, magnetite, ilmenite, two unidentified (new?) Fe-silicates and recrystallized later aenigmatite-II. Apparently hosting pegmatite ...

© Pavel M. Kartashov collection & photo

One of the largest arfvedsonite crystals from this locality. Have been found in the quartz core of alkali granite pegmatite. Specimen of Yaroslav Shelepov, 2013. Photos are copyright free for non-commercial/educational uses. Just credit photos to Andrey Vishnevskiy/Novosibirsk State University.

© Andrey Vishnevskiy

Prismatic crystals of black Nb-bearing Chevkinite-(Ce) in epidote-quartz metasomatites of the deposit. The largest crystal length is 2 cm. Some of Chevkinite crystals has greenish-grey outer rims composed by oriented Hydroxylsynchysite-(Ce)-Rutile mixture - product of their late-hydrothermal alteration. This metasomatite was appear after Ca ...

© Pavel M. Kartashov collection & photo

Black rosettes of Ferriallanite-(Ce) and brown platelets of Ferristilpnomelane in Quartz-Epidote metasomatites after alkaline granite pegmatite. FOV is ~12x10 mm. Selfcollected in 1990 on the Eastern ore zone of the locality. Pavel M. Kartashov collection and photo.

© Pavel M. Kartashov collection & photo

3 mm group of Hinnganite-(Ce) dipyramidal crystals, etched from filled with calcite cavity in epidote-quartz metasomatites, formed by replacement of rare metal alcaline granitic pegmatite. Such Hingganite is Fe-free and enriched with Nd up to formation of zones of Nd-dominant Hingganite-(Nd). Mineral is covered by yellow spherulitic ...

© Pavel M. Kartashov collection & photo

Largest arfvedsonite crystal from this locality. Taking into account the dimentions ratio, maybe this is the largest arfvedsonite crystal ever found. Have been found in the quartz core of alkali granite pegmatite. Specimen of Maria Cherdantseva, 2013. SEM verified. Photos are copyright free for non-commercial/educational uses. Just credit ...

© Andrey Vishnevskiy

Pinkish-red crystals of Aluminocerite-(Ce) (IMA2007-060) into cavity on the border of quartz and intergrowth of black chevkinite-(Ce) and brown metamict glue-like fergusonite-(Y). FOV is ~4x3.5 mm. Selfcollected in the trench #2 of Western ore zone of the deposit in July 1990. Pavel M. Kartashov collection and photo.

© Pavel M. Kartashov collection & photo

3 and 1.5 mm long flattened-prismatic crystals of Fersmite in cavity of Epidote-Quartz metasomatites. Initially the cavity was filled with Calcite, which was dissolved. Collected by A.D. Babanskii in 1990 on Western ore zone dumps. Pavel M. Kartashov collection and photo.

© Pavel M. Kartashov collection & photo

5 mm long typical Zircon crystal from cavity in epidote-quartz metasomatites of the locality. Calcite was dissolved from this cavity. Associating minerals are green Epidote, Quartz and brownish grain of Fergusonite-(Y). Collected in trench #2 of Western ore zone in 1990. Pavel M. Kartashov collection and photo.

© Pavel M. Kartashov collection and photo

Pinkish-red grains of Aluminocerite-(Ce) (IMA2007-060) in fibrous whitish fersmite-synchysite-titanite crust of alteration of black niobian chevkinite-(Ce). Brownish crystals of zircon and green ones of epidote are visible. Selfcollected in the trench #2 of Western ore zone of the deposit in July 1990. Pavel M. Kartashov collection and photo.

© Pavel M. Kartashov collection & photo

Pinkish-red crystals of aluminocerite (IMA2007-060) into cavity on the border of large crystal of chevkinite-(Ce) and epidote. White crusts are the secondary calcite. FOV ~5x4 mm. Selfcollected in the trench #2 of Western ore zone of the deposit in July 1990. Pavel M. Kartashov collection and photo.

© Pavel M. Kartashov collection & photo

Large broken grain of black niobian Chevkinite-(Ce) from rare-metal alkaline pegmatite. Associated minerals are: brown lustrous grain of fergusonite-(Y), pink masses of small crystals of aluminocerite-(Ce) (IMA2007-060), dark-grey veinlets of allanite-(Ce) in quartz. Microscopic hingganites-(Ce), -(Y) and -(Nd) (unvisible according to their small ...

© Pavel M. Kartashov collection & photo

colourles grains of Hinnganite-(Ce) on greenish-black Allanite-(Ce) In Coll. M. Slama (ex Coll. P. Kartashov) Canon EOS 600D with Canon MP-E 65mm f/2.8 1-5x, stacked from 18 Images using Zerene Stacker (Pmax)

© Martin Slama