The Distribution of Rare Metals in the LCT Pegmatites from the Giraúl Field, Angola
Abstract
:1. Introduction
2. Geology
2.1. Regional Geology
2.2. Pegmatite Types
2.2.1. Type-I Pegmatites
2.2.2. Type-II Pegmatites
2.2.3. Type-III Pegmatites
2.2.4. Type-IV Pegmatites
2.2.5. Type-V Pegmatites
3. Analytical Methods
4. Mineralogy of the Giraúl Pegmatites
4.1. Mineralogical Composition and Textural Patterns
4.1.1. Textural Patterns of Zircon
4.1.2. Textural Patterns of the Nb-Ta Oxide Minerals
4.1.3. Textural Patterns of Cassiterite
4.2. Mineral Chemistry
4.2.1. Zircon
4.2.2. Columbite-Group Minerals
4.2.3. Stibiocolumbite and Stibiotantalite
4.2.4. Pyrochlore Supergroup
4.2.5. Rutile Group
4.2.6. Cassiterite
4.2.7. Uraninite
5. Discusion
5.1. Evolution of Zircon in the Giraúl Pegmatites
5.2. Evolution of the Nb-Ta Oxide Minerals in the Giraúl Pegmatites at Crystal Scale
5.3. Evolution in the Composition of the Nb-Ta Oxides at Field Scale
5.4. Comparison of the Nb-Ta Fractionation Trend with Other Pegmatite Fields
5.5. Mechanisms of Concentration of Nb and Ta
6. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Type | I | II | III | III | III | IV | IV | IV | V | V |
---|---|---|---|---|---|---|---|---|---|---|
Zone | 1st I | 1st I | 1st | 2nd I | 3rd I | Border | 1st | 2nd I | Border | 3rd I |
Sample | X2B | GP13 | Ibep3 | I + 4B | pa8–4 | a21–10 | a6a | A10ap17 | k100q | K100C |
SiO2 | 31.22 | 31.57 | 32.27 | 31.67 | 30.91 | 31.13 | 31.75 | 31.15 | 31.21 | 31.03 |
TiO2 | 0.02 | 0.00 | 0.01 | 0.02 | 0.00 | 0.03 | 0.05 | 0.04 | 0.03 | 0.00 |
ZrO2 | 61.38 | 65.86 | 65.29 | 63.17 | 63.71 | 64.72 | 60.33 | 56.93 | 67.05 | 56.12 |
HfO2 | 2.56 | 2.15 | 1.39 | 3.32 | 4.69 | 1.68 | 5.66 | 11.89 | 1.38 | 11.54 |
ThO2 | 0.00 | 0.00 | 0.07 | 0.04 | 0.08 | 0.00 | 0.00 | 0.04 | 0.09 | 0.00 |
Al2O3 | 0.53 | 0.00 | 0.00 | 0.00 | 0.00 | 0.05 | 0.25 | 0.02 | 0.00 | 0.00 |
Y2O3 | 0.29 | 0.17 | 0.10 | 1.38 | 0.00 | 0.21 | 1.31 | 0.00 | 0.00 | 0.00 |
U2O3 | 0.88 | 0.12 | 0.16 | 0.00 | 0.35 | 0.17 | 0.00 | 0.01 | 0.00 | 0.00 |
CaO | 0.05 | 0.01 | 0.02 | 0.03 | 0.00 | 0.10 | 0.21 | 0.00 | 0.03 | 0.09 |
FeO | 2.07 | 0.07 | 0.26 | 0.01 | 0.03 | 0.42 | 0.15 | 0.00 | 0.16 | 0.09 |
Total | 99.91 | 99.95 | 99.57 | 99.64 | 99.77 | 98.51 | 99.71 | 100.08 | 99.95 | 98.87 |
Apfu * | ||||||||||
Si | 0.53 | 0.98 | 1.00 | 0.99 | 0.97 | 0.98 | 1.00 | 1.00 | 0.97 | 1.00 |
Zr | 0.51 | 1.00 | 0.98 | 0.96 | 0.98 | 0.99 | 0.92 | 0.89 | 1.01 | 0.89 |
Hf | 0.01 | 0.02 | 0.01 | 0.03 | 0.04 | 0.02 | 0.05 | 0.11 | 0.01 | 0.11 |
Al | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 |
Y | 0.00 | 0.00 | 0.00 | 0.02 | 0.00 | 0.00 | 0.02 | 0.00 | 0.00 | 0.00 |
U | 0.92 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
Ca | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 |
Fe | 0.03 | 0.00 | 0.01 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 |
Zr/Hf | 40.96 | 52.33 | 80.24 | 32.50 | 23.21 | 65.81 | 18.21 | 8.18 | 83.00 | 8.31 |
Type | II | III | III | III | IV | IV | IV | IV | V | V | V | V | V |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Zone | 2nd I | 3rd I | 3rd I | 3rd I | 1st I | 1st I | 2nd I | 2nd I | 1st I | 1st I | 2nd I | 3rd I | 3rd I |
Sample | GP1 | PA8 | P8 | P8 | D1e | A41c | A9Db | A10F | k40 | k40 | K100C | K100L | K100R |
Mineral | FT | MC | MC | MT | MT | FC | MT | FC | FC | FC | FC | FC | FC |
WO3 | 0.30 | 2.40 | 0.52 | 0.40 | n.a. | 1.49 | 0.35 | 0.00 | 0.67 | 0.50 | n.a. | 1.03 | 1.08 |
Ta2O5 | 53.32 | 10.81 | 24.61 | 56.93 | 52.26 | 9.28 | 58.75 | 12.65 | 26.35 | 42.03 | 39.97 | 26.62 | 11.86 |
Nb2O5 | 27.08 | 65.53 | 54.93 | 25.06 | 29.34 | 68.25 | 24.29 | 67.16 | 52.86 | 39.65 | 41.70 | 52.20 | 64.86 |
TiO2 | 0.29 | 1.70 | 0.95 | 0.51 | 1.23 | 1.23 | 0.26 | 0.22 | 0.87 | 0.33 | 0.32 | 1.05 | 1.77 |
UO2 | 0.02 | 0.13 | 0.00 | 0.03 | n.a | 0.12 | n.a. | 0.08 | 0.07 | n.a. | 0.00 | n.a. | n.a. |
Y2O3 | 0.00 | n.a. | n.a. | n.a. | 0.01 | 0.09 | n.a. | 1.02 | n.a. | n.a. | 0.37 | 0.73 | 0.72 |
SnO2 | 0.10 | 0.38 | 0.20 | 0.26 | 0.01 | 0.14 | 0.21 | 0.05 | 0.57 | 0.17 | 0.16 | 0.24 | 0.07 |
Fe2O3 | 0.63 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.06 | 0.00 | 0.00 | 0.00 | 0.70 | 1.71 |
FeO | 8.13 | 9.00 | 8.75 | 7.48 | 7.79 | 14.48 | 2.71 | 14.04 | 13.24 | 9.43 | 10.49 | 14.19 | 14.53 |
MnO | 7.57 | 10.28 | 9.11 | 7.74 | 8.46 | 4.65 | 12.71 | 5.50 | 4.79 | 7.60 | 6.90 | 3.59 | 3.69 |
MgO | 0.00 | 0.03 | 0.03 | 0.16 | n.a. | 0.06 | 0.03 | n.a. | 0.04 | 0.00 | n.a. | 0.13 | 0.18 |
Sb2O3 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.02 | 0.00 | 0.06 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
PbO | 0.00 | 0.18 | |||||||||||
Total | 97.44 | 100.26 | 99.10 | 98.57 | 99.29 | 99.81 | 99.31 | 100.78 | 99.46 | 99.71 | 99.91 | 100.48 | 100.47 |
Atomic | contents | ||||||||||||
W6+ | 0.023 | 0.019 | 0.034 | 0.031 | - | 0.090 | 0.027 | - | 0.044 | 0.035 | - | 0.067 | 0.065 |
Ta5+ | 4.268 | 0.699 | 1.675 | 4.556 | 4.046 | 0.589 | 4.715 | 0.808 | 1.806 | 3.092 | 2.904 | 1.805 | 0.750 |
Nb5+ | 3.604 | 7.049 | 6.214 | 3.334 | 3.776 | 7.196 | 3.240 | 7.132 | 6.024 | 4.848 | 5.037 | 5.883 | 6.822 |
Ti2+ | 0.064 | 0.304 | 0.179 | 0.113 | 0.263 | 0.216 | 0.058 | 0.039 | 0.165 | 0.067 | 0.064 | 0.197 | 0.310 |
U4+ | 0.001 | 0.007 | 0.000 | 0.002 | - | 0.006 | - | 0.004 | 0.004 | - | 0.000 | - | - |
Y3+ | 0.000 | - | - | - | 0.002 | 0.011 | - | 0.128 | - | - | 0.053 | 0.097 | 0.089 |
Sn4+ | 0.012 | 0.036 | 0.020 | 0.034 | 0.001 | 0.013 | 0.025 | 0.005 | 0.057 | 0.018 | 0.017 | 0.024 | 0.006 |
Fe3+ | 0.140 | 0.000 | 0.000 | 0.000 | 0.002 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.131 | 0.299 |
Fe2+ | 2.001 | 1.791 | 1.831 | 1.841 | 1.855 | 2.824 | 0.669 | 2.758 | 2.791 | 2.133 | 2.344 | 2.958 | 2.827 |
Mn2+ | 1.887 | 2.072 | 1.931 | 1.929 | 2.040 | 0.919 | 3.177 | 1.094 | 1.023 | 1.741 | 1.562 | 0.758 | 0.727 |
Mg2+ | 0.000 | 0.018 | 0.019 | 0.116 | - | 0.035 | 0.022 | - | 0.025 | 0.000 | 0.000 | 0.080 | 0.104 |
Sb3+ | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.002 | 0.000 | 0.006 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 |
Pb2+ | 0.000 | 0.000 | 0.000 | 0.000 | 0.014 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 |
CATSUM | 12.000 | 11.994 | 11.901 | 11.955 | 12.000 | 11.901 | 11.932 | 11.974 | 11.940 | 11.935 | 11.981 | 12.000 | 12.000 |
Ta/(Ta + Nb) | 0.542 | 0.090 | 0.212 | 0.577 | 0.517 | 0.076 | 0.593 | 0.102 | 0.231 | 0.389 | 0.366 | 0.235 | 0.099 |
Mn/(Mn + Fe) | 0.469 | 0.536 | 0.513 | 0.512 | 0.523 | 0.245 | 0.826 | 0.284 | 0.268 | 0.449 | 0.400 | 0.197 | 0.189 |
Type | III | III | III | IV | IV | V | V | V | V |
---|---|---|---|---|---|---|---|---|---|
Mineral | OBP | HPP | OUP | HPP | HKP | FNM | ONM | FNM | HSP |
Sample | P-5 | P-10 | P-11 | A33b | A11A | K100-20 | K100C46 | K100C32 | K100L |
WO3 | 0.00 | 2.59 | 0.79 | 1.10 | 4.14 | n.a. | n.a. | n.a. | 1.19 |
Nb2O5 | 35.04 | 16.37 | 30.16 | 26.59 | 45.49 | 18.53 | 11.24 | 25.40 | 24.23 |
Ta2O5 | 5.23 | 22.86 | 5.32 | 18.20 | 17.80 | 58.29 | 55.74 | 48.42 | 19.45 |
TiO2 | 1.88 | 5.70 | 2.96 | 4.40 | 1.11 | 0.40 | 0.71 | 0.30 | 10.51 |
SnO0 | 0.31 | 0.72 | 0.38 | 0.17 | 0.24 | 0.19 | 3.08 | 0.29 | 0.72 |
ThO2 | 0.00 | n.a. | n.a. | 0.07 | 0.00 | n.a. | n.a. | n.a. | 0.00 |
UO2 | 8.39 | 0.00 | 36.31 | 1.90 | 0.08 | 0.15 | 14.88 | 0.25 | 0.00 |
Sc2O3 | 0.00 | 0.06 | 0.11 | 0.10 | 0.36 | n.a. | n.a. | n.a. | 0.32 |
Y2O3 | 0.23 | 0.00 | 0.00 | n.a. | 0.80 | 0.00 | 0.00 | 0.31 | 0.00 |
Sb2O3 | 0.34 | 0.60 | 0.00 | 0.48 | 19.98 | 0.55 | 0.65 | 0.92 | 25.92 |
Bi2O3 | 21.04 | 0.00 | 0.00 | n.a. | 0.00 | 0.04 | 0.20 | 0.00 | 0.00 |
CaO | 1.73 | 1.07 | 2.19 | 0.03 | 0.00 | 9.50 | 5.65 | 10.45 | 0.03 |
MnO | 0.56 | 0.69 | 0.48 | 0.15 | 0.11 | 0.17 | 0.00 | 0.14 | 0.10 |
FeO | 4.35 | 1.56 | 1.84 | 1.09 | 0.55 | 0.65 | 0.04 | 0.40 | 1.32 |
SrO | 0.00 | 0.00 | 0.00 | n.a. | 0.00 | 2.71 | 0.85 | 1.96 | 0.81 |
BaO | 0.13 | n.a. | n.a. | 0.14 | 0.00 | n.a. | n.a. | n.a. | 0.00 |
PbO | 3.06 | 46.11 | 8.37 | 44.56 | 0.29 | 0.09 | 1.34 | 0.08 | 9.34 |
Na2O | 0.05 | 0.22 | 0.20 | 0.14 | 3.72 | 5.52 | 3.87 | 6.47 | 0.56 |
K2O | 0.16 | 0.00 | 0.19 | 0.03 | 0.14 | 0.00 | 0.01 | 0.05 | 0.00 |
F | 0.01 | 0.00 | 0.30 | 0.23 | 0.00 | 5.23 | 0.79 | 5.84 | 0.16 |
OH | 1.19 | 0.00 | 2.12 | 2.79 | 0.00 | 0.18 | 0.00 | 1.95 | |
O=F | −0.01 | 0.00 | −0.15 | −0.12 | 0.00 | −2.62 | −0.40 | −2.92 | −0.08 |
Total | 82.51 | 99.74 | 89.45 | 101.38 | 97.60 | 99.40 | 98.84 | 98.36 | 96.53 |
apfu | |||||||||
W6+ | 0.000 | 0.077 | 0.025 | 0.030 | 0.084 | - | - | - | 0.027 |
Nb | 1.696 | 0.795 | 1.555 | 1.168 | 1.501 | 0.683 | 0.489 | 0.923 | 0.895 |
Ta | 0.152 | 0.668 | 0.165 | 0.481 | 0.353 | 1.292 | 1.460 | 1.059 | 0.432 |
Ti | 0.151 | 0.460 | 0.254 | 0.321 | 0.061 | 0.025 | 0.051 | 0.018 | 0.646 |
ΣB site | 2.000 | 2.000 | 2.000 | 2.000 | 2.000 | 2.000 | 2.000 | 2.000 | 2.000 |
Sn4+ | 0.015 | 0.035 | 0.019 | 0.007 | 0.008 | 0.007 | 0.132 | 0.010 | 0.026 |
Th | 0.000 | - | - | 0.002 | 0.000 | - | - | - | 0.000 |
U | 0.200 | 0.000 | 0.922 | 0.041 | 0.001 | 0.003 | 0.319 | 0.004 | 0.000 |
Sc | 0.000 | 0.006 | 0.011 | 0.008 | 0.023 | - | - | - | 0.023 |
Y | 0.013 | 0.000 | 0.000 | 0.000 | 0.031 | 0.000 | 0.000 | 0.013 | 0.000 |
Sb | 0.015 | 0.027 | 0.000 | 0.019 | 0.601 | 0.018 | 0.026 | 0.030 | 0.873 |
Bi | 0.581 | 0.000 | 0.000 | 0.000 | 0.000 | 0.001 | 0.005 | 0.000 | 0.000 |
Ca | 0.198 | 0.123 | 0.268 | 0.003 | 0.000 | 0.830 | 0.583 | 0.900 | 0.003 |
Mn2+ | 0.051 | 0.063 | 0.046 | 0.012 | 0.007 | 0.012 | 0.000 | 0.010 | 0.007 |
Fe2+ | 0.389 | 0.140 | 0.176 | 0.089 | 0.034 | 0.044 | 0.003 | 0.027 | 0.090 |
Sr | 0.000 | 0.000 | 0.000 | - | 0.000 | 0.128 | 0.047 | 0.091 | 0.038 |
Ba | 0.006 | - | - | 0.005 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 |
Pb | 0.088 | 1.333 | 0.257 | 1.165 | 0.006 | 0.002 | 0.035 | 0.002 | 0.205 |
Na | 0.010 | 0.046 | 0.044 | 0.026 | 0.527 | 0.873 | 0.723 | 1.009 | 0.089 |
K | 0.022 | 0.000 | 0.028 | 0.004 | 0.013 | 0.000 | 0.001 | 0.005 | 0.000 |
ΣA site | 1.589 | 1.772 | 1.770 | 1.382 | 1.250 | 1.917 | 1.874 | 2.102 | 1.354 |
F | 0.003 | 0.000 | 0.108 | 0.071 | 0.000 | 1.348 | 0.241 | 1.485 | 0.041 |
OH | 0.000 | 0.853 | 0.000 | 1.375 | 1.360 | 0.000 | 0.116 | 0.000 | 1.064 |
oxygen | 6.997 | 6.147 | 7.492 | 5.554 | 5.640 | 5.807 | 6.644 | 5.871 | 5.895 |
ΣYsite | 7.000 | 7.000 | 7.600 | 7.000 | 7.000 | 7.155 | 7.000 | 7.356 | 7.000 |
Zone | 1st I | 2nd I | ||||
---|---|---|---|---|---|---|
Sample | A33a | A33b | D1E | D1E | D1E | D1E |
Mineral | Nbrt | Nbrt | Nbrt | Nbrt | Nbrt | Tart |
WO3 | n.a. | n.a. | 3.36 | 1.89 | 1.08 | 2.40 |
Nb2O5 | 7.35 | 10.32 | 21.56 | 13.32 | 16.79 | 9.78 |
Ta2O5 | 6.90 | 8.94 | 33.47 | 19.87 | 10.54 | 26.14 |
TiO2 | 79.94 | 74.20 | 28.48 | 55.81 | 62.88 | 49.17 |
SnO2 | 0.00 | 0.00 | 0.00 | 0.04 | 0.00 | 0.05 |
UO2 | 0.00 | 0.00 | 0.12 | 0.01 | 0.09 | 0.05 |
Y2O3 | 0.00 | 0.00 | 0.04 | 0.00 | 0.14 | 0.43 |
MgO | 0.00 | 0.00 | 0.10 | 0.02 | 0.02 | 0.15 |
MnO | 0.02 | 0.03 | 4.35 | 0.31 | 0.33 | 1.19 |
Fe2O3 | 4.80 | 5.33 | 9.85 | 9.72 | 9.18 | 10.23 |
Total | 99.01 | 98.82 | 101.33 | 100.99 | 101.05 | 99.59 |
apfu | ||||||
W6+ | - | - | 0.052 | 0.025 | 0.014 | 0.034 |
Nb | 0.144 | 0.207 | 0.542 | 0.288 | 0.344 | 0.224 |
Ta | 0.081 | 0.108 | 0.506 | 0.259 | 0.130 | 0.360 |
Ti | 2.601 | 2.473 | 1.192 | 2.008 | 2.140 | 1.875 |
Sn4+ | 0.000 | 0.000 | 0.000 | 0.001 | 0.000 | 0.001 |
U4+ | 0.000 | 0.000 | 0.001 | 0.000 | 0.001 | 0.001 |
Y3+ | 0.000 | 0.000 | 0.001 | 0.000 | 0.003 | 0.012 |
Mg | 0.000 | 0.000 | 0.008 | 0.001 | 0.001 | 0.011 |
Mn2+ | 0.001 | 0.001 | 0.205 | 0.013 | 0.013 | 0.051 |
Fe3+ | 0.156 | 0.178 | 0.413 | 0.350 | 0.313 | 0.391 |
Cat.Sum | 2.983 | 2.966 | 2.921 | 2.945 | 2.958 | 2.960 |
Type | IV | V | |||||||
---|---|---|---|---|---|---|---|---|---|
Zone | 2nd I | 1st I | 2nd I | 3rd I | |||||
Sample | A11a | i4 + b | K40 | K40 | K100B | K100B | K100d | kK00d | K100L |
WO3 | 0.04 | 0.00 | 0.00 | 0.00 | n.a. | n.a | 0.3 | 0.53 | 0.19 |
Nb2O5 | 0.37 | 0.05 | 0.37 | 0.37 | 1.04 | 0.11 | 0.00 | 0.44 | 0.00 |
Ta2O5 | 0.79 | 0.38 | 2.32 | 1.79 | 5.53 | 3.38 | 0.98 | 3.76 | 0.19 |
TiO2 | 0.23 | 1.32 | 0.2 | 0.26 | 0.13 | 0.08 | 0.08 | 0.12 | 0.27 |
SnO2 | 98.59 | 98.48 | 96.53 | 97.32 | 91.63 | 95.51 | 99.48 | 95.68 | 99.36 |
UO2 | 0.11 | 0.06 | n.a | n.a | n.a. | n.a | n.a | 0.00 | 0.00 |
MgO | 0.20 | 0.18 | 0.05 | 0.08 | 0.09 | 0.05 | 0.17 | 0.12 | 0.14 |
MnO | 0.08 | 0.04 | 0 | 0 | 0.04 | 0.07 | 0.05 | 0.06 | 0.00 |
Fe2O3 | 0.47 | 0.45 | 0.52 | 0.43 | 1.32 | 0.79 | 0.2 | 0.86 | 0.16 |
Total | 100.88 | 100.97 | 99.99 | 100.25 | 99.78 | 99.99 | 101.26 | 101.57 | 100.31 |
apfu | |||||||||
W6+ | 0.001 | 0.000 | 0.000 | 0.000 | - | - | 0.004 | 0.007 | 0.003 |
Nb | 0.008 | 0.001 | 0.008 | 0.008 | 0.024 | 0.003 | 0.000 | 0.010 | 0.000 |
Ta | 0.011 | 0.005 | 0.032 | 0.024 | 0.076 | 0.046 | 0.013 | 0.051 | 0.003 |
Ti | 0.009 | 0.049 | 0.008 | 0.010 | 0.005 | 0.003 | 0.003 | 0.004 | 0.010 |
Sn4+ | 1.948 | 1.927 | 1.930 | 1.938 | 1.842 | 1.917 | 1.963 | 1.888 | 1.974 |
U4+ | 0.003 | 0.001 | - | - | - | - | - | 0.000 | 0.000 |
Mg | 0.015 | 0.013 | 0.004 | 0.006 | 0.007 | 0.004 | 0.013 | 0.009 | 0.010 |
Mn2+ | 0.003 | 0.002 | 0.000 | 0.000 | 0.002 | 0.003 | 0.002 | 0.003 | 0.000 |
Fe2+ | 0.018 | 0.017 | 0.020 | 0.016 | 0.050 | 0.030 | 0.008 | 0.032 | 0.006 |
Cat, Sum | 2.015 | 2.015 | 2.002 | 2.003 | 2.004 | 2.006 | 2.006 | 2.003 | 2.006 |
© 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
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Gonçalves, A.O.; Melgarejo, J.-C.; Alfonso, P.; Amores, S.; Paniagua, A.; Neto, A.B.; Morais, E.A.; Camprubí, A. The Distribution of Rare Metals in the LCT Pegmatites from the Giraúl Field, Angola. Minerals 2019, 9, 580. https://doi.org/10.3390/min9100580
Gonçalves AO, Melgarejo J-C, Alfonso P, Amores S, Paniagua A, Neto AB, Morais EA, Camprubí A. The Distribution of Rare Metals in the LCT Pegmatites from the Giraúl Field, Angola. Minerals. 2019; 9(10):580. https://doi.org/10.3390/min9100580
Chicago/Turabian StyleGonçalves, Antonio Olimpio, Joan-Carles Melgarejo, Pura Alfonso, Sandra Amores, Andrés Paniagua, Andrés Buta Neto, Eduardo Alves Morais, and Antoni Camprubí. 2019. "The Distribution of Rare Metals in the LCT Pegmatites from the Giraúl Field, Angola" Minerals 9, no. 10: 580. https://doi.org/10.3390/min9100580