Daubréelite, Troilite, Iron (Var: Kamacite)

Specimen ID: E01-V8U

Mineral(s)
Daubréelite : Fe2+Cr3+2S4
Troilite : FeS
Iron (Var: Kamacite) : (Fe,Ni)
Locality
As recorded:
Chinga meteorite, Chinge River, Tuva, Russia
Mindat locality:
Events

Photo added to mindat.org

SEM image of polished section. Darkmost in BSE exsolution lamellae of Daubreelite within more bright Troilite. The brightmost tabular crystal is low-nickeloan (6.35 mas.% Ni, 1.16 mas.% Co) Kamacite. Analytical data available at the daughter photo. Pavel M. Kartashov analytical data, collection and photo.
Pavel Kartashov - 31st August 2017

Photo added to mindat.org

SEM image of polished section under smaller magnification than for the previous picture. Whole grain of Troilite within bright high-nickeloan (16.62 mas.% Ni, 0.98 mas.% Co) Kamacite. Darkmost in BSE phase is Goethite - product oxidation of Trolilite. Dark grey exsolution lamellae of Daubreelite forms wavy lines within light-grey Troilite matrix. The brightmost tabular crystals in Troilite-Daubreelite aggregate are low-nickeloan (6.35 mas.% Ni, 1.16 mas.% Co) Kamacite. Analytical data available at the daughter photo. Pavel M. Kartashov analytical data, collection and photo.
Pavel Kartashov - 31st August 2017

Photo added to mindat.org

SEM image of polished section under smaller magnification than for the previous picture. Two grains of Troilite within bright high-nickeloan (16.62 mas.% Ni, 0.98 mas.% Co) Kamacite. The upper tabular grain don't contains Daubreelite lamellae and is significantly replaced by darkmost in BSE Goethite. Along sides within the grain the brightmost elongated crystals of Taenite are visible. The lower isometric grain is composed by Troilite-Daubreelite aggregate with minor Goethite and low-nickeloan (6.35 mas.% Ni, 1.16 mas.% Co) Kamacite inclusions. Pavel M. Kartashov analytical data, collection and photo.
Pavel Kartashov - 31st August 2017

Photo added to mindat.org

Polished side of slice of the ataxite meteorite. Close to its center two grains of Troilite from previous SEM image are visible. Pavel M. Kartashov analytical data, collection and scan.
Pavel Kartashov - 31st August 2017

Photo added to mindat.org

EDX spectra of associating Daubreelite (the upper) and Trolite (the lower) from Chinge meteorite. Daubreelite from Chinge meteorite contains excess of Fe3+ and admixtures of V (0.09-0.12 mas.%) and Mn (0.62-0.74 mas.%). It is interesting that troilite and nickeloan iron matrix don't contains Mn. Empirical formula of this Daubreelite is (Fe0.96Mn0.04)1.00(Cr1.83Fe0.26V0.01)2.10S3.90. Troilite matrix still contains some chromium (3.66 mas.%) and vanadium (0.73 mas.%) even after exsolution of Daubreelite phase. Composition of this Troilite is (Fe0.89Cr0.06V0.01)0.96S1.04. Pavel M. Kartashov analytical data, collection and photo.
Pavel Kartashov - 31st August 2017

Photo added to mindat.org

EDX spectra of nickeloan iron phases from Chinge meteorite. The upper spectrum belongs to lamel of low-nickeloan Kamacite from Daubreelite-Troilite aggregate. It composition is (Fe0.92Ni0.07Co0.01). Intermediate - to high-nickeloan Kamacite from the main body of the meteorite - (Fe0.82Ni0.17Co0.01). The lover spectrum obtained from Taenite grain from endocontact of Troilite tabular crystal - (Fe0.74Ni0.25Co0.01). Pavel M. Kartashov analytical data, collection and photo.
Pavel Kartashov - 31st August 2017

Mindat.org Photo of the Day

Pavel Kartashov - 30th October 2017
Liked by
No-one has added this to their favourites.
Log in to comment/edit
10,443,628 minIDs have been issued as of 27th Apr 2024 2:04 pm UTC