Chromite-PGM Mineralization in the Lherzolite Mantle Tectonite of the Kraka Ophiolite Complex (Southern Urals, Russia)
Abstract
:1. Introduction
2. Analytical Techniques
3. Geological Setting
3.1. Regional Geological Background
3.2. Local Geology of the Kraka Massif
4. Podiform Chromite Deposits of the Kraka Ophiolite
4.1. Occurrence
4.2. Chromite Texture and Composition
4.3. Solid Inclusions in Chromite
4.4. Composition of the Chromitite Parent Melt
4.5. The Temperature and Oxygen Fugacity of the Chromitite Forming System
5. PGM in Chromitites of the Kraka Mantle Tectonite
5.1. PGM Mineralogy and Composition
5.2. Origin of Primary PGM as a Function of ƒ(S2)
5.3. PGM Reworking at Low Temperature
6. Discussion
7. Summary and Conclusions
- The studied podiform chromite deposits of the Kraka lherzolite massif occur in two distinct positions of the mantle stratigraphy: the shallow one (BB) is located in a harzburgite horizon, just below the mantle/crust transition zone; the other (Prospect 33) is seated deep in the mantle tectonite. Both deposits consist of high-Cr chromitite (Cr# = 0.70–0.83) similar to boninite-derived chromitites in ophiolite complexes, and are surrounded by a dunite envelope, indicating a reaction between wall-rock residual mantle and adiabatically ascending melts ([14] and references therein). The chromite/olivine equilibrium reflects a rapid cooling rate in the shallow deposit (T = 1300–1100 °C) that did not enable an increase in sulfur fugacity above logƒS2 = −3.0, yielding very limited Ru-Os PGM mineralization (mainly laurite). In the deep-seated deposit, a slow cooling rate allowed closure of the chromite crystallization system between 1100 °C and 800 °C, and slightly higher sulfur fugacity, logƒ(S2) > +1.0, could developed, producing a more complex assemblage of laurite, erlichmanite, and Ir sulfides now occurring as inclusions in chromite crystals.
- The chondrite-normalized PGE patterns of the Bolshoi Bashart chromitite overlap in terms of chondritic abundance and the distribution of PGE in chromitites from the Alapaevsk and Kluchevskoy ophiolite massifs, now exposed the East-Uralian zone (Figure 1B). This zone is the easternmost region of the Urals that contains ophiolite blocks with chromite deposits, usually intermixed with granites and fragments of continental crust that may indicate a paleogeographic location proximal to a continental block in the eastern side of the Uralian Ocean [8,34].
- In contrast with the large ophiolite complexes of the western Uralian basin hosted in the HOT ophiolites, the mantle tectonite such as Kraka, of the LOT ophiolite contains only small and medium-size deposits of high-Cr chromitite with a minor transition to high-Al ore. Ages dating back to Precambrian have been proposed for accretion of the suboceanic lithosphere at Alapaevsk [27], possibly indicating that intensive intra-oceanic thrusts and subduction did not start yet in this epoch in this part of the basin. The fact that the chromitites contain only laurite-type mineralization, similarly to Kraka, is a clear indication of low sulfur fugacity and fluid depleted composition of the percolating melts [12]. Therefore, deep mantle metasomatism responsible for the formation of the giant deposits of the Urals (Kempirsai, Ray-Iz) was hampered. The occurrence of the high-Cr deposit inside lherzolite type mantle tectonite remains a quite isolated case in the Urals, possible representing a case of chromitite probably associated with a continental margin type ophiolite.
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Sample | BB7612 | BB7615 | BB7616 | BB7618 | BB7619 | BB X1 | BB X2 | BB X3 | PE1754 | PE1755 | PE1757 | PE1758 | PE1764 |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Ore type | mas | mas | mas | mas | mas | mas | dis | mas | nod | mas | mas | nod | micro-nod |
n° anal. | (6) | (6) | (14) | (6) | (26) | (5) | (10) | (8) | (20) | (20) | (20) | (20) | (20) |
SiO2 | 0.02 | 0.01 | 0.00 | 0.06 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
TiO2 | 0.17 | 0.14 | 0.21 | 0.15 | 0.16 | 0.17 | 0.15 | 0.23 | 0.18 | 0.19 | 0.21 | 0.19 | 0.12 |
Al2O3 | 12.03 | 11.37 | 14.98 | 11.98 | 13.99 | 12.77 | 10.77 | 10.72 | 8.35 | 9.90 | 10.38 | 8.85 | 8.23 |
FeO | 11.48 | 11.41 | 10.94 | 11.56 | 12.25 | 11.56 | 12.80 | 11.94 | 10.45 | 10.70 | 11.68 | 11.84 | 10.23 |
Fe2O3 | 3.20 | 4.67 | 4.88 | 4.62 | 5.49 | 4.62 | 3.30 | 3.26 | 5.22 | 5.03 | 4.35 | 4.66 | 5.42 |
MgO | 14.42 | 14.33 | 15.07 | 14.27 | 14.48 | 14.45 | 13.51 | 13.97 | 14.61 | 14.52 | 14.14 | 13.78 | 14.66 |
MnO | 0.15 | 0.22 | 0.23 | 0.17 | 0.26 | 0.21 | 0.30 | 0.24 | 0.34 | 0.31 | 0.40 | 0.40 | 0.38 |
Cr2O3 | 57.53 | 57.17 | 52.69 | 55.81 | 54.36 | 55.46 | 58.89 | 58.48 | 60.03 | 58.05 | 58.71 | 59.69 | 60.05 |
NiO | 0.16 | 0.15 | 0.00 | 0.09 | 0.01 | 0.08 | 0.00 | 0.00 | 0.10 | 0.12 | 0.11 | 0.07 | 0.09 |
ZnO | 0.03 | 0.13 | 0.00 | 0.12 | 0.00 | 0.06 | 0.00 | 0.00 | 0.02 | 0.03 | 0.02 | 0.02 | 0.02 |
V2O3 | 0.11 | 0.07 | 0.00 | 0.08 | 0.01 | 0.05 | 0.00 | 0.00 | 0.03 | 0.03 | 0.02 | 0.04 | 0.03 |
Total | 99.31 | 99.67 | 99.02 | 98.91 | 101.01 | 99.44 | 99.72 | 98.85 | 99.33 | 98.88 | 100.03 | 99.54 | 99.23 |
Cr# | 0.76 | 0.77 | 0.70 | 0.76 | 0.72 | 0.74 | 0.79 | 0.79 | 0.83 | 0.80 | 0.79 | 0.82 | 0.83 |
Mg# | 0.69 | 0.69 | 0.71 | 0.69 | 0.68 | 0.69 | 0.65 | 0.68 | 0.71 | 0.71 | 0.68 | 0.67 | 0.72 |
Fe3+# | 0.04 | 0.06 | 0.06 | 0.06 | 0.06 | 0.06 | 0.04 | 0.04 | 0.06 | 0.06 | 0.05 | 0.06 | 0.07 |
Sample | BB7619 | BB X 1 | BB X 2 | BB X 3 | BB X 4 | BB X 5 | BB X 6 | BB X 7 | BB X 8 | PE1758 | PE1758 | PE1754 | PE1764 |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
n° anal. | (12) | - | - | - | - | - | - | - | - | (2) | (55) | (4) | (28) |
SiO2 | 41.13 | 40.97 | 41.26 | 40.84 | 41.69 | 42.89 | 43.23 | 41.10 | 40.91 | 49.22 | 41.77 | 47.10 | 41.46 |
TiO2 | 0.01 | 0.00 | 0.00 | 0.02 | 0.01 | 0.00 | 0.01 | 0.02 | 0.01 | 0.00 | 0.05 | 0.03 | 0.04 |
Al2O3 | 0.04 | 0.06 | 0.05 | 0.02 | 0.00 | 0.01 | 0.00 | 0.02 | 0.00 | 0.41 | 0.00 | 0.00 | 0.01 |
FeO | 6.85 | 6.87 | 7.01 | 7.08 | 6.73 | 2.50 | 2.70 | 7.01 | 6.84 | 1.91 | 2.93 | 2.98 | 2.56 |
MgO | 50.89 | 51.01 | 50.68 | 50.24 | 50.69 | 52.55 | 51.44 | 50.26 | 50.72 | 45.66 | 52.75 | 47.26 | 51.98 |
MnO | 0.09 | 0.10 | 0.07 | 0.09 | 0.10 | 0.02 | 0.04 | 0.09 | 0.07 | 0.08 | 0.04 | 0.05 | 0.03 |
CaO | 0.04 | 0.04 | 0.04 | 0.06 | 0.02 | 0.00 | 0.00 | 0.01 | 0.00 | 0.04 | 0.01 | 0.01 | 0.02 |
Na2O | 0.11 | 0.01 | 0.03 | 0.19 | 0.17 | 0.00 | 0.00 | 0.06 | 0.05 | 0.04 | 0.01 | 0.00 | 0.01 |
K2O | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.18 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 |
Cr2O3 | 0.02 | 0.00 | 0.08 | 0.01 | 0.00 | 0.47 | 0.15 | 0.00 | 0.00 | 0.01 | 0.52 | 0.66 | 1.03 |
NiO | 0.33 | 0.31 | 0.38 | 0.26 | 0.34 | 0.78 | 0.75 | 0.26 | 0.33 | 0.33 | 0.82 | 1.07 | 0.95 |
ZnO | 0.05 | 0.00 | 0.07 | 0.07 | 0.05 | 0.11 | 0.00 | 0.07 | 0.09 | 0.00 | 0.00 | 0.00 | 0.00 |
V2O3 | 0.00 | 0.00 | 0.02 | 0.00 | 0.00 | 0.02 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
Total | 99.56 | 99.37 | 99.70 | 98.88 | 99.80 | 99.33 | 98.32 | 99.08 | 99.04 | 97.69 | 98.90 | 99.16 | 98.09 |
Fo% | 93.0 | 93.0 | 92.8 | 92.7 | 93.1 | 97.4 | 97.1 | 92.7 | 93.0 | 97.7 | 97.0 | 96.6 | 97.3 |
Clinopyroxene | Amphibole | |||||||||
---|---|---|---|---|---|---|---|---|---|---|
Sample | PE1754 | PE1755 | PE1757 | PE1757b | PE1758 | PE1757 | PE1757 | PE1757 | PE1757b | PE1757b |
texture | included | included | included | included | included | included | included | included | included | included |
n° anal. | (3) | (40) | (17) | (3) | (7) | - | - | - | - | - |
SiO2 | 54.76 | 54.72 | 54.87 | 55.50 | 55.22 | 47.87 | 48.59 | 48.64 | 52.54 | 53.89 |
TiO2 | 0.02 | 0.11 | 0.09 | 0.20 | 0.17 | 0.55 | 0.28 | 0.34 | 0.23 | 0.42 |
Al2O3 | 1.14 | 1.27 | 1.32 | 0.99 | 1.02 | 7.87 | 7.67 | 8.27 | 7.81 | 8.99 |
FeO | 1.39 | 1.29 | 1.36 | 1.13 | 1.43 | 1.35 | 1.40 | 1.50 | 1.12 | 1.58 |
MgO | 15.00 | 14.26 | 17.05 | 15.59 | 17.42 | 20.04 | 20.37 | 20.51 | 16.35 | 10.84 |
MnO | 0.02 | 0.04 | 0.04 | 0.04 | 0.03 | 0.05 | 0.01 | 0.02 | 0.04 | 0.02 |
CaO | 22.56 | 23.43 | 22.76 | 23.82 | 22.82 | 12.37 | 12.32 | 12.26 | 13.67 | 14.33 |
Na2O | 0.86 | 0.53 | 0.85 | 0.67 | 0.76 | 2.66 | 2.69 | 2.64 | 2.49 | 2.29 |
K2O | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.16 | 0.14 | 0.16 | 0.13 | 0.01 |
Cr2O3 | 2.63 | 2.55 | 2.38 | 2.04 | 2.26 | 4.08 | 3.31 | 3.55 | 2.84 | 3.62 |
NiO | 0.05 | 0.07 | 0.06 | 0.02 | 0.06 | 0.24 | 0.22 | 0.18 | 0.21 | 0.23 |
Total | 98.42 | 98.27 | 100.78 | 100.00 | 101.18 | 97.22 | 97.01 | 98.07 | 97.43 | 96.21 |
Chromite | Melt | ||||||
---|---|---|---|---|---|---|---|
n° anal. | Cr# | TiO2 | FeO/MgO | Al2O3 | TiO2 | FeO/MgO | |
Kraka deposit 33 | 5 | 0.81 | 0.18 | 0.77 | 12.14 | 0.53 | 0.56 |
Kraka Bolshoi Bashart deposit BB | 7 | 0.76 | 0.19 | 0.83 | 13.00 | 0.55 | 0.64 |
High-Cr chromite deposits in Ophiolitic mantle tectonite of the Urals (§) | |||||||
Voykar Syninsky | 10 | 0.80 | 0.14 | 1.15 | 10.78 | 0.23 | 0.85 |
Verkhneivinsky | 1 | 0.83 | 0.14 | 1.49 | 10.21 | 0.23 | 1.11 |
Ray-Iz | 46 | 0.80 | 0.10 | 0.89 | 10.81 | 0.19 | 0.66 |
Kempirsai | 170 | 0.81 | 0.16 | 0.76 | 10.84 | 0.26 | 0.56 |
Kluchevskoyoy | 58 | 0.76 | 0.19 | 1.10 | 11.71 | 0.29 | 0.83 |
Alapaevsk | 121 | 0.79 | 0.21 | 1.09 | 11.24 | 0.32 | 0.80 |
Spinels in Modern volcanic suites (§) | |||||||
MORB (Mid oceanic ridge basalt) | 18 | 0.56 | 0.57 | 0.76 | 15.99 | 1.10 | 0.91 |
BAB (Back-arc basalt) | 1 | 0.45 | 0.41 | 0.60 | 17.72 | 1.29 | 0.80 |
OIB (Oceanic-island basalt) | 1 | 0.76 | 1.39 | 1.34 | 11.93 | 2.19 | 0.85 |
IAB (Island-arc high-K, calc-alkaline basalt) | 5 | 0.83 | 0.41 | 0.97 | 10.87 | 0.53 | 0.69 |
IABon IAT (Island-arc boninite, tholeiite) | 4 | 0.90 | 0.15 | 0.87 | 8.18 | 0.26 | 0.57 |
LIP (Large igneous provinces flood basalts) | 3 | 0.81 | 3.02 | 1.78 | 7.98 | 3.39 | 0.81 |
W. Greenland flood basalt | 1 | 0.69 | 0.97 | 1.32 | 14.69 | 1.84 | 1.36 |
Ankaramite | 7 | 0.82 | 0.55 | 1.23 | 9.65 | 0.69 | 1.03 |
Chromite | Olivine | ||||||
---|---|---|---|---|---|---|---|
Sample | Mg# | Cr# | Fe3/Fe2 + Fe3 | Fo% | T°C | Δlogƒ(O2) | |
BB7619-12 | 0.70 | 0.75 | 0.27 | 93.0 | 1271 | 1.248 | |
BB X 2 | 0.68 | 0.79 | 0.20 | 92.9 | 1256 | 1.137 | |
BB X 1 | 0.65 | 0.79 | 0.19 | 92.9 | 1165 | 0.473 | |
BB7619-11 | 0.66 | 0.75 | 0.19 | 93.0 | 1090 | 0.386 | |
PE1754 | 0.71 | 0.83 | 0.31 | 96.6 | 1060 | 2.636 | |
PE1764 | 0.72 | 0.83 | 0.32 | 97.3 | 982 | 3.076 | |
PE1758 | 0.67 | 0.82 | 0.26 | 97.0 | 891 | 2.281 | |
PE1758 | 0.67 | 0.82 | 0.26 | 97.7 | 809 | 2.670 |
BB7615 | BB7618 | BB7612 | BB7616 | BB7619 | |
---|---|---|---|---|---|
Os | 9.64 | 10.70 | 12.20 | 13.00 | 8.76 |
Ir | 6.30 | 10.30 | 8.83 | 9.89 | 5.78 |
Ru | 27.30 | 29.10 | 24.90 | 28.40 | 23.60 |
Rh | 4.06 | 4.88 | 3.76 | 4.02 | 3.21 |
Pt | 0.60 | 1.72 | 0.98 | 1.10 | 0.89 |
Pd | 1.00 | 1.18 | 1.12 | 0.87 | 0.91 |
Au | 0.50 | 0.56 | 0.61 | 0.48 | 0.50 |
ΣPGE | 48.9 | 57.88 | 51.79 | 57.28 | 43.15 |
Pd/Ir | 0.159 | 0.115 | 0.127 | 0.088 | 0.157 |
PPGE/IPGE | 0.131 | 0.155 | 0.128 | 0.117 | 0.131 |
Sample Label | Mineral | Os | Ir | Ru | Rh | Pt | Pd | Fe | Ni | Cu | S | As | Total |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Sulfides of the laurite-erlichmanite series | |||||||||||||
BB Y | Laurite | 14.26 | 6.61 | 39.13 | 0.83 | 0.57 | 0.08 | 36.54 | 0.99 | 99.01 | |||
BB Y | Laurite | 16.40 | 6.15 | 41.65 | 0.12 | 0.20 | 0.24 | 0.02 | 34.87 | 99.65 | |||
BB7617 1 | Laurite | 27.90 | 2.32 | 31.89 | 0.56 | 0.40 | 1.33 | 0.04 | 0.07 | 32.83 | 0.52 | 97.86 | |
BB7617 1a 1 | Laurite | 28.97 | 3.99 | 33.86 | 0.13 | 0.13 | 31.42 | 98.50 | |||||
BB7617 1a 1 | Laurite | 26.71 | 2.22 | 30.53 | 0.53 | 0.00 | 0.38 | 1.27 | 0.04 | 0.07 | 31.43 | 0.49 | 93.68 |
BB7617 1a 2 | Laurite | 28.98 | 4.15 | 35.35 | 0.05 | 0.18 | 31.34 | 100.05 | |||||
BB7617 1b 1 | Laurite | 18.85 | 13.48 | 31.82 | 2.12 | 0.05 | 0.00 | 0.25 | 0.20 | 32.89 | 0.03 | 99.69 | |
BB7617 1b 1 * | Laurite | 16.88 | 12.73 | 29.63 | 2.48 | 0.00 | 0.82 | 1.84 | 0.17 | 0.47 | 33.27 | 1.70 | 100.00 |
BB7617 2 | Laurite | 16.34 | 12.32 | 28.69 | 2.40 | 0.79 | 1.78 | 0.17 | 0.46 | 32.21 | 1.65 | 96.81 | |
BB7617 3 | Laurite | 28.96 | 3.99 | 33.86 | 0.13 | 0.13 | 31.42 | 0.91 | 99.40 | ||||
BB7617 4 | Laurite | 28.10 | 3.14 | 35.00 | 0.05 | 0.17 | 31.30 | 0.50 | 98.26 | ||||
BB7617 5 | Laurite | 18.85 | 13.48 | 31.82 | 2.12 | 0.05 | 0.24 | 0.20 | 32.89 | 0.05 | 99.70 | ||
BB7618 1 | Laurite | 13.28 | 6.66 | 44.25 | 0.00 | 0.00 | 0.12 | 0.21 | 0.10 | 33.81 | 0.06 | 98.49 | |
BB7618 1 1 * | Laurite | 14.50 | 6.76 | 44.96 | 0.00 | 0.00 | 0.00 | 0.12 | 0.22 | 0.11 | 33.33 | 0.00 | 100.00 |
BB7618 1a 1 * | Laurite | 12.14 | 5.63 | 33.31 | 0.72 | 0.00 | 0.49 | 15.25 | 0.12 | 0.40 | 31.09 | 0.84 | 100.00 |
BB7618 2 | Laurite | 14.48 | 6.16 | 39.82 | 0.85 | 0.73 | 1.28 | 0.01 | 0.29 | 34.19 | 0.15 | 97.96 | |
BB7618 2 1 | Laurite | 16.40 | 6.15 | 41.65 | 0.12 | 0.20 | 0.25 | 0.03 | 34.87 | 99.68 | |||
BB7618 2a 1 | Laurite | 13.68 | 4.59 | 37.07 | 0.86 | 0.00 | 0.54 | 1.58 | 0.08 | 0.12 | 32.59 | 0.91 | 92.02 |
BB7618 3 | Laurite | 14.57 | 4.89 | 39.48 | 0.92 | 0.58 | 1.08 | 0.07 | 0.13 | 34.70 | 0.95 | 97.37 | |
BB7618 4 | Laurite | 16.40 | 6.14 | 41.65 | 0.12 | 0.20 | 0.24 | 0.02 | 34.87 | 99.64 | |||
BB7619 1 | Laurite | 13.31 | 7.18 | 40.13 | 0.89 | 0.59 | 1.70 | 0.07 | 0.12 | 34.50 | 0.69 | 99.18 | |
BB7619 1 1 | Laurite | 15.76 | 7.34 | 39.04 | 0.28 | 0.15 | 0.35 | 0.08 | 33.09 | 96.10 | |||
BB7619 1a 1 * | Laurite | 12.52 | 6.75 | 37.76 | 0.84 | 0.00 | 0.56 | 3.83 | 0.80 | 0.13 | 35.71 | 1.11 | 100.00 |
BB7619 1a 2 * | Laurite | 13.12 | 6.63 | 38.71 | 0.65 | 0.00 | 0.51 | 3.41 | 0.84 | 0.16 | 35.00 | 0.97 | 100.00 |
BB7619 2 | Laurite | 14.02 | 7.08 | 41.38 | 0.70 | 0.55 | 1.51 | 0.11 | 0.15 | 34.03 | 0.94 | 100.47 | |
BB7619 4 | Laurite | 15.76 | 7.34 | 39.04 | 0.27 | 0.15 | 0.35 | 0.08 | 33.09 | 96.08 | |||
BB7618 1a 2 * | Laurite | 13.29 | 5.65 | 36.55 | 0.78 | 0.00 | 0.67 | 9.12 | 0.13 | 0.32 | 32.67 | 0.80 | 100.00 |
PE1754a 1 | Laurite | 7.79 | 3.66 | 37.63 | 12.28 | 0.42 | 33.70 | 1.26 | 96.74 | ||||
PE1754a 2 | Laurite | 17.61 | 4.46 | 40.53 | 0.26 | 0.42 | 33.28 | 0.50 | 97.06 | ||||
PE1758a 1 | Laurite | 5.88 | 14.57 | 38.56 | 1.25 | 0.72 | 32.68 | 2.74 | 96.40 | ||||
PE1758a 2 | Laurite | 5.42 | 14.83 | 38.98 | 1.50 | 0.30 | 32.49 | 2.71 | 96.23 | ||||
PE1758a 3 | Laurite | 5.56 | 14.64 | 39.35 | 1.27 | 0.49 | 32.24 | 2.57 | 96.12 | ||||
PE1759 * | Laurite | 29.09 | 4.76 | 24.78 | 0.00 | 0.00 | 0.00 | 1.72 | 0.60 | 4.80 | 33.01 | 1.24 | 100.00 |
PE1759 * | Laurite | 32.13 | 5.17 | 27.71 | 0.00 | 0.00 | 0.00 | 0.75 | 0.00 | 1.03 | 33.20 | 0.00 | 100.00 |
PE1757 1 | Erlichmanite | 34.97 | 15.94 | 17.72 | 0.84 | 0.38 | 27.47 | 1.08 | 98.40 | ||||
Primary and secondary sulfides and arsenides | |||||||||||||
PE1759 * | Un. (NiFePt)9S8 | 0.00 | 0.00 | 0.00 | 0.00 | 1.09 | 0.00 | 3.63 | 61.96 | 0.00 | 33.32 | 0.00 | 100.00 |
BB7619 3 | Ru-pentlandite | 3.61 | 1.42 | 8.48 | 0.29 | 0.12 | 11.78 | 42.28 | 0.17 | 31.95 | 0.15 | 100.25 | |
BB7619 3 * | Ru-pentlandite | 3.68 | 1.45 | 9.65 | 0.30 | 0.13 | 0.00 | 8.94 | 43.01 | 0.18 | 32.50 | 0.16 | 100.00 |
PE1755 * | Un. Ni3As | 0.00 | 11.45 | 1.92 | 5.06 | 0.00 | 0.00 | 0.00 | 55.34 | 0.00 | 0.00 | 26.22 | 100.00 |
Primary and secondary alloys | |||||||||||||
PE1757b 1 | Rutheniridosmine | 44.01 | 4.64 | 47.68 | 0.00 | 0.00 | 0.29 | 96.62 | |||||
PE1757b 2 | Rutheniridosmine | 44.04 | 5.40 | 47.84 | 0.00 | 0.00 | 0.19 | 97.47 | |||||
PE1755 * | Ruteniridosmine | 55.19 | 14.18 | 22.37 | 0.00 | 0.00 | 0.00 | 2.94 | 5.32 | 0.00 | 0.00 | 0.00 | 100.00 |
PE1755 * | Ruthenium | 0.00 | 10.47 | 60.34 | 0.00 | 0.00 | 0.00 | 9.18 | 20.01 | 0.00 | 0.00 | 0.00 | 100.00 |
BB X | Awaruite | 0.39 | 0.22 | 0.46 | 25.25 | 71.01 | 0.09 | 0.38 | 97.80 | ||||
PE1755 * | Garutiite | 0.00 | 39.73 | 0.00 | 0.00 | 0.00 | 0.00 | 3.75 | 53.84 | 2.69 | 0.00 | 0.00 | 100.00 |
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Garuti, G.; Pushkarev, E.V.; Gottman, I.A.; Zaccarini, F. Chromite-PGM Mineralization in the Lherzolite Mantle Tectonite of the Kraka Ophiolite Complex (Southern Urals, Russia). Minerals 2021, 11, 1287. https://0-doi-org.brum.beds.ac.uk/10.3390/min11111287
Garuti G, Pushkarev EV, Gottman IA, Zaccarini F. Chromite-PGM Mineralization in the Lherzolite Mantle Tectonite of the Kraka Ophiolite Complex (Southern Urals, Russia). Minerals. 2021; 11(11):1287. https://0-doi-org.brum.beds.ac.uk/10.3390/min11111287
Chicago/Turabian StyleGaruti, Giorgio, Evgenii V. Pushkarev, Irina A. Gottman, and Federica Zaccarini. 2021. "Chromite-PGM Mineralization in the Lherzolite Mantle Tectonite of the Kraka Ophiolite Complex (Southern Urals, Russia)" Minerals 11, no. 11: 1287. https://0-doi-org.brum.beds.ac.uk/10.3390/min11111287