Gem-Quality Tourmaline from LCT Pegmatite in Adamello Massif, Central Southern Alps, Italy: An Investigation of Its Mineralogy, Crystallography and 3D Inclusions
Abstract
1. Introduction
2. Background Information
3. Geological Setting
4. Materials and Methods
5. Results
5.1. Gemmological Properties and 3D Visualisation of the Tourmaline Inclusions
5.2. Chemical Composition
5.3. X-Ray Crystal Structure Refinement
6. Discussion and Conclusions
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Sample | Cavity Name/Description * | Colour | Analytical Techniques | |
---|---|---|---|---|
1 | Cavity 1 | Pink | Electron microprobe (WDS) (°) | Single crystal XRD (°) |
2 | Cavity boulder 2 | Light blue | Electron microprobe (WDS) (°) | Single crystal XRD (°) |
3 | Pizio cavity | Colourless to brown | Electron microprobe (WDS) (°) | |
4: sample cut perpendicular to the c-axis | Pizio cavity | Pink green | Electron microprobe (WDS) (°) | |
5 | Cavity 3 | Light green yellow | Electron microprobe (WDS) (°) | |
6 | Cavity 4 | Yellow to colourless | Electron microprobe (WDS) (°) | |
7 | Cavity 5 | Synchrotron X-ray computed μ-tomography | ||
8 | Cavity 6 | Synchrotron X-ray computed μ-tomography | ||
9 | “Black quartz” cavity | Pink green | Electron microprobe (WDS) (°) | |
10: double terminated sample | Inv.# M36742 cavity | Browm green | Electron microprobe (WDS) (°) | |
11: homologous terminated sample | Inv.# M36742 cavity | Green to colourless | Electron microprobe (WDS) (°) | |
12: sample cut perpendicular to the c-axis | Inv.# M36742 cavity | Blue | Electron microprobe (WDS) (°) | Single crystal XRD (°) |
13 | Cut stone (0.731 ct) from pocket | Green brown | Specific gravity | Refractive index |
14 | Cut stone (0.848 ct) from pocket | Green brown | Specific gravity | Refractive index |
15 | Cut stone (0.838 ct) from pocket | Green brown | Specific gravity | Refractive index |
16 | Cut stone (1.225 ct) from pocket | Pale green | Specific gravity | Refractive index |
Sample | 1 | 2 | 3a | 3b | 4 | 5 | ||||||||||
Pink Elbaite | Pink Rossmanite | Pink Elbaite | Pink Rossmanite | Light Blue Elbaite | Colourless Elbaite | Brown Elbaite | Rim-Green Elbaite | Core-Pink Elbaite | Core-Pink Elbaite | Core-Pink Elbaite | Inter-Pink Elbaite | Rim-Green Elbaite | Elbaite | Light Green Elbaite | ||
Average (20 pts) | Average (10 pts) | Average (15 pts) | Average (20 pts) | |||||||||||||
Point Number ° | 4 | 6 | 8 | 9 | 16 | 10 | 24 | 23 | 56 | 54 | 33 | |||||
SiO2 (wt %) | 36.34 | 36.63 | 36.28 | 37.06 | 36.2 | 36.17 | 36.54 | 36.99 | 36.79 | 36.67 | 36.59 | 37.04 | 37.28 | 36.71 | 36.29 | |
TiO2 | bdl | bdl | 0.06 | bdl | 0.03 | 0.03 | 0.07 | 0.04 | bdl | bdl | 0.04 | bdl | 0.02 | 0.24 | 0.03 | |
B2O3 * | 11.06 | 11.18 | 11.02 | 11.27 | 10.78 | 10.87 | 10.77 | 10.98 | 10.94 | 10.93 | 10.91 | 11.04 | 11.05 | 10.64 | 10.9 | |
Al2O3 | 43.3 | 44.73 | 42.95 | 44.91 | 38.83 | 40.28 | 37.86 | 40.32 | 41.41 | 41.36 | 41.34 | 42.14 | 40.72 | 36.01 | 40.16 | |
V2O3 | 0.02 | bdl | bdl | bdl | 0.01 | bdl | 0.02 | 0.02 | 0.02 | bdl | bdl | 0.01 | bdl | 0.04 | 0.01 | |
Cr2O3 | bdl | bdl | bdl | bdl | 0.02 | 0.01 | bdl | bdl | bdl | 0.03 | 0.01 | 0.03 | bdl | 0.01 | bdl | |
FeO | 0.02 | bdl | bdl | 0.03 | 1.00 | 0.73 | 1.43 | 0.83 | bdl | bdl | 0.01 | 0.01 | 0.52 | 4.75 | 0.77 | |
MgO | 0.03 | bdl | bdl | 0.01 | 0.02 | 0.02 | 0.01 | 0.01 | bdl | 0.01 | 0.01 | 0.01 | bdl | bdl | 0.01 | |
MnO | 0.52 | 0.21 | 0.55 | 0.27 | 3.79 | 2.79 | 3.99 | 2.82 | 0.16 | 0.16 | 0.13 | 0.12 | 2.02 | 2.45 | 2.93 | |
ZnO | 0.09 | bdl | bdl | bdl | 0.05 | 0.03 | 0.08 | bdl | 0.14 | 0.08 | 0.05 | 0.03 | 0.10 | 0.50 | 0.05 | |
CaO | 0.95 | 0.28 | 0.98 | 0.27 | 1.08 | 0.98 | 1.23 | 0.78 | 1.52 | 1.65 | 1.57 | 1.23 | 1.27 | 0.36 | 1.18 | |
Li2O * | 1.87 | 1.74 | 1.91 | 1.75 | 1.73 | 1.77 | 1.76 | 1.76 | 2.12 | 2.16 | 2.15 | 2.09 | 1.95 | 1.5 | 1.80 | |
Na2O | 1.38 | 1.39 | 1.42 | 1.35 | 2.19 | 2.05 | 2.25 | 1.98 | 1.26 | 1.29 | 1.31 | 1.39 | 1.72 | 2.73 | 1.98 | |
K2O | 0.01 | bdl | 0.01 | 0.01 | 0.02 | 0.02 | 0.01 | 0.01 | 0.01 | 0.01 | 0.02 | bdl | bdl | 0.03 | 0.01 | |
H2O* | 3.53 | 3.83 | 3.53 | 3.78 | 3.12 | 3.27 | 3.13 | 3.24 | 3.22 | 3.24 | 3.17 | 3.34 | 3.26 | 3.00 | 3.24 | |
F | 0.61 | 0.07 | 0.57 | 0.24 | 1.27 | 1.00 | 1.25 | 1.16 | 1.17 | 1.11 | 1.25 | 0.98 | 1.16 | 1.41 | 1.10 | |
Total | 99.73 | 100.07 | 99.27 | 100.94 | 100.13 | 100.02 | 100.48 | 100.95 | 98.77 | 98.7 | 98.57 | 99.45 | 101.08 | 100.39 | 100.47 | |
O=F | 0.26 | 0.03 | 0.24 | 0.1 | 0.53 | 0.42 | 0.53 | 0.49 | 0.49 | 0.47 | 0.53 | 0.41 | 0.49 | 0.59 | 0.46 | |
Total * | 99.47 | 100.04 | 99.03 | 100.84 | 99.6 | 99.6 | 99.96 | 100.46 | 98.27 | 98.23 | 98.04 | 99.04 | 100.59 | 99.79 | 100 | |
Structural formula based on 31 anions (O, OH, F) | ||||||||||||||||
Si | 5.71 | 5.692 | 5.723 | 5.714 | 5.835 | 5.783 | 5.905 | 5.856 | 5.846 | 5.831 | 5.829 | 5.831 | 5.864 | 5.996 | 5.788 | |
Al | 0.29 | 0.308 | 0.277 | 0.286 | 0.165 | 0.217 | 0.097 | 0.144 | 0.154 | 0.169 | 0.171 | 0.169 | 0.136 | 0.004 | 0.212 | |
T sum | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | |
B | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | |
Al (Z) | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | |
Cr | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | |
Al | 1.727 | 1.884 | 1.709 | 1.875 | 1.211 | 1.373 | 1.081 | 1.379 | 1.601 | 1.583 | 1.59 | 1.65 | 1.413 | 0.928 | 1.336 | |
Ti | - | - | 0.007 | 0.001 | 0.004 | 0.004 | 0.012 | 0.005 | - | - | 0.004 | - | 0.002 | 0.03 | 0.004 | |
V | 0.003 | - | - | - | 0.001 | 0.001 | 0.002 | 0.002 | 0.003 | - | - | 0.001 | - | 0.006 | 0.001 | |
Cr | - | - | - | - | 0.002 | 0.001 | 0.001 | - | bdl | 0.004 | 0.002 | 0.003 | - | 0.001 | - | |
Mg | 0.007 | 0.001 | - | 0.002 | 0.004 | 0.004 | 0.003 | 0.003 | bdl | 0.003 | 0.003 | 0.002 | - | - | 0.003 | |
Mn | 0.069 | 0.028 | 0.073 | 0.035 | 0.518 | 0.377 | 0.527 | 0.378 | 0.022 | 0.021 | 0.017 | 0.016 | 0.269 | 0.339 | 0.396 | |
Fe2+ | 0.003 | - | - | 0.003 | 0.134 | 0.097 | 0.231 | 0.11 | 0.001 | - | 0.001 | 0.001 | 0.069 | 0.649 | 0.102 | |
Zn | 0.01 | - | - | - | 0.006 | 0.004 | 0.013 | - | 0.016 | 0.009 | 0.006 | 0.003 | 0.012 | 0.061 | 0.006 | |
Li * | 1.181 | 1.087 | 1.212 | 1.084 | 1.12 | 1.139 | 1.129 | 1.122 | 1.358 | 1.38 | 1.375 | 1.325 | 1.235 | 0.987 | 1.151 | |
Y sum | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | |
Ca | 0.159 | 0.046 | 0.165 | 0.044 | 0.187 | 0.168 | 0.201 | 0.132 | 0.259 | 0.281 | 0.268 | 0.207 | 0.214 | 0.064 | 0.202 | |
Na | 0.42 | 0.419 | 0.434 | 0.404 | 0.684 | 0.635 | 0.707 | 0.608 | 0.388 | 0.396 | 0.406 | 0.424 | 0.525 | 0.865 | 0.613 | |
K | 0.002 | - | 0.002 | 0.003 | 0.004 | 0.003 | 0.003 | 0.003 | 0.002 | 0.002 | 0.004 | - | - | 0.005 | 0.002 | |
Vacancy | 0.418 | 0.535 | 0.399 | 0.55 | 0.125 | 0.194 | 0.089 | 0.257 | 0.351 | 0.32 | 0.322 | 0.368 | 0.261 | 0.066 | 0.183 | |
X sum | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | |
OH | 3.695 | 3.967 | 3.715 | 3.884 | 3.353 | 3.492 | 3.363 | 3.419 | 3.412 | 3.442 | 3.37 | 3.512 | 3.423 | 3.272 | 3.445 | |
F | 0.305 | 0.033 | 0.285 | 0.116 | 0.647 | 0.508 | 0.637 | 0.581 | 0.588 | 0.558 | 0.63 | 0.488 | 0.577 | 0.728 | 0.555 | |
Sample | 6 | 9a | 9b | 10 | 11 | 12 | ||||||||||
Analogous Green | Antilogous Dark Green | |||||||||||||||
Light Yellow Elbaite | Light Yellow Elbaite | Light Yellow Fluor-Liddicoatite | Colourless Flour-Liddicoatite | Pink Elbaite | Green Elbaite | Foitite | Elbaite | Elbaite | Elbaite | Fluor-Liddicoatite | Elbaite | Elbaite | Rossmanite | Green Elbaite | Blue Elbaite | |
Average (9 pts) | Average (10 pts) | Average (21 pts) | Average (20 pts) | |||||||||||||
Point Number ° | 4 | 10 | 12 | 36 | 42 | 43 | 45 | |||||||||
SiO2 (wt %) | 35.70 | 36.00 | 36.71 | 37.50 | 37.12 | 37.32 | 35.82 | 37.38 | 38.13 | 37.51 | 37.60 | 37.82 | 37.13 | 37.06 | 36.95 | 37.10 |
TiO2 | 0.14 | 0.17 | 0.09 | 0.09 | 0.01 | 0.17 | bdl | bdl | bdl | 0.18 | 0.03 | 0.05 | 0.20 | 0.07 | 0.18 | 0.17 |
B2O3 * | 10.84 | 10.83 | 10.94 | 10.99 | 11.07 | 11.00 | 10.39 | 10.92 | 11.09 | 11.02 | 10.99 | 11.04 | 10.98 | 10.76 | 10.96 | 10.93 |
Al2O3 | 40.53 | 39.68 | 39.90 | 39.43 | 41.59 | 39.78 | 33.55 | 39.33 | 39.60 | 39.74 | 39.03 | 40.09 | 39.60 | 37.57 | 39.86 | 39.30 |
V2O3 | 0.01 | 0.04 | 0.01 | bdl | 0.01 | 0.02 | bdl | 0.03 | bdl | 0.10 | 0.02 | bdl | 0.04 | bdl | 0.01 | bdl |
Cr2O3 | bdl | bdl | bdl | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | bdl | bdl | 0.02 | bdl | 0.05 | bdl | 0.01 | 0.01 |
FeO | 0.34 | 0.54 | 0.22 | 0.16 | 0.08 | 0.71 | 11.52 | 1.68 | 0.44 | 0.85 | 0.34 | 0.88 | 1.25 | 3.40 | 1.18 | 0.66 |
MgO | 0.01 | 0.01 | 0.01 | bdl | 0.01 | 0.01 | 2.57 | 0.03 | 0.01 | 0.01 | 0.02 | 0.05 | 0.04 | 0.02 | 0.03 | 0.03 |
MnO | 2.38 | 2.51 | 1.29 | 0.99 | 1.60 | 2.05 | 0.17 | 3.68 | 1.82 | 1.82 | 1.45 | 2.89 | 1.87 | 5.67 | 2.31 | 3.10 |
ZnO | bdl | bdl | 0.08 | bdl | 0.03 | 0.06 | 0.10 | 0.12 | 0.12 | 0.02 | 0.08 | 0.09 | 0.19 | 0.18 | 0.02 | 0.03 |
CaO | 1.49 | 1.58 | 2.67 | 2.94 | 1.16 | 1.53 | 0.02 | 0.13 | 1.96 | 1.62 | 3.05 | 0.27 | 1.47 | 0.07 | 1.00 | 1.21 |
Li2O * | 1.90 | 1.97 | 2.31 | 2.44 | 1.96 | 2.05 | 0.14 | 1.45 | 2.20 | 2.05 | 2.38 | 1.71 | 1.98 | 0.91 | 1.87 | 1.88 |
Na2O | 1.81 | 1.97 | 1.32 | 1.05 | 1.59 | 1.77 | 1.48 | 1.97 | 1.50 | 1.54 | 0.99 | 2.10 | 1.84 | 1.37 | 2.08 | 1.88 |
K2O | bdl | 0.02 | 0.01 | bdl | 0.01 | 0.01 | 0.01 | 0.01 | bdl | 0.01 | 0.01 | bdl | 0.01 | 0.02 | 0.02 | 0.02 |
H2O * | 3.29 | 3.17 | 3.23 | 3.21 | 3.39 | 3.25 | 3.58 | 3.77 | 3.45 | 3.22 | 3.18 | 3.81 | 3.28 | 3.71 | 3.33 | 3.22 |
F | 0.95 | 1.19 | 1.16 | 1.23 | 0.91 | 1.14 | bdl | bdl | 0.79 | 1.23 | 1.29 | bdl | 1.08 | bdl | 0.95 | 1.17 |
Total | 99.39 | 99.67 | 99.94 | 100.03 | 100.54 | 100.88 | 99.37 | 100.52 | 101.11 | 100.90 | 100.49 | 100.81 | 101.00 | 100.82 | 100.77 | 100.70 |
O=F | 0.40 | 0.50 | 0.49 | 0.52 | 0.38 | 0.48 | bdl | bdl | 0.33 | 0.52 | 0.54 | bdl | 0.45 | bdl | 0.40 | 0.49 |
Total * | 98.99 | 99.17 | 99.46 | 99.52 | 100.16 | 100.40 | 99.37 | 100.52 | 100.78 | 100.38 | 99.95 | 100.81 | 100.55 | 100.82 | 100.37 | 100.21 |
Structural formula based on 31 anions (O, OH, F) | ||||||||||||||||
Si | 5.726 | 5.779 | 5.831 | 5.931 | 5.830 | 5.894 | 5.994 | 5.948 | 5.978 | 5.918 | 5.946 | 5.952 | 5.875 | 5.985 | 5.858 | 5.898 |
Al | 0.274 | 0.221 | 0.169 | 0.069 | 0.170 | 0.106 | 0.006 | 0.052 | 0.022 | 0.082 | 0.054 | 0.048 | 0.125 | 0.015 | 0.142 | 0.102 |
T sum | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 |
B | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 |
Al (Z) | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 | 6.000 |
Cr | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
Al | 1.387 | 1.287 | 1.301 | 1.282 | 1.528 | 1.299 | 0.612 | 1.323 | 1.296 | 1.307 | 1.220 | 1.387 | 1.260 | 1.136 | 1.305 | 1.263 |
Ti | 0.017 | 0.020 | 0.011 | 0.010 | 0.001 | 0.020 | - | - | - | 0.021 | 0.004 | 0.006 | 0.024 | 0.008 | 0.022 | 0.020 |
V | 0.002 | 0.005 | 0.001 | - | 0.001 | 0.002 | - | 0.004 | - | 0.012 | 0.003 | - | 0.005 | - | 0.001 | 0.001 |
Cr | - | - | - | 0.001 | 0.001 | 0.001 | 0.002 | 0.001 | - | - | 0.003 | - | 0.006 | - | 0.001 | 0.001 |
Mg | 0.004 | 0.003 | 0.003 | 0.001 | 0.001 | 0.003 | 0.641 | 0.008 | 0.002 | 0.002 | 0.005 | 0.012 | 0.009 | 0.006 | 0.008 | 0.007 |
Mn | 0.323 | 0.341 | 0.173 | 0.133 | 0.213 | 0.275 | 0.024 | 0.496 | 0.242 | 0.243 | 0.194 | 0.385 | 0.251 | 0.776 | 0.310 | 0.417 |
Fe2+ | 0.046 | 0.072 | 0.029 | 0.021 | 0.010 | 0.093 | 1.612 | 0.224 | 0.058 | 0.112 | 0.045 | 0.116 | 0.165 | 0.459 | 0.157 | 0.087 |
Zn | - | - | 0.010 | - | 0.004 | 0.007 | 0.013 | 0.014 | 0.014 | 0.002 | 0.010 | 0.010 | 0.022 | 0.022 | 0.003 | 0.003 |
Li * | 1.223 | 1.271 | 1.473 | 1.552 | 1.240 | 1.299 | 0.096 | 0.930 | 1.389 | 1.300 | 1.517 | 1.083 | 1.259 | 0.594 | 1.193 | 1.200 |
Y sum | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 |
Ca | 0.256 | 0.272 | 0.454 | 0.498 | 0.195 | 0.259 | 0.003 | 0.022 | 0.329 | 0.274 | 0.517 | 0.046 | 0.249 | 0.012 | 0.171 | 0.207 |
Na | 0.563 | 0.613 | 0.407 | 0.321 | 0.485 | 0.542 | 0.480 | 0.608 | 0.456 | 0.471 | 0.303 | 0.641 | 0.564 | 0.429 | 0.640 | 0.581 |
K | 0.001 | 0.003 | 0.002 | 0.000 | 0.002 | 0.002 | 0.002 | 0.002 | - | 0.001 | 0.002 | - | 0.003 | 0.003 | 0.003 | 0.004 |
Vacancy | 0.181 | 0.112 | 0.137 | 0.180 | 0.317 | 0.197 | 0.515 | 0.368 | 0.214 | 0.254 | 0.179 | 0.313 | 0.184 | 0.555 | 0.187 | 0.209 |
X sum | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 |
OH | 3.519 | 3.396 | 3.417 | 3.385 | 3.547 | 3.429 | 4.000 | 4.000 | 3.608 | 3.386 | 3.355 | 4.000 | 3.460 | 4.000 | 3.522 | 3.412 |
F | 0.481 | 0.604 | 0.583 | 0.615 | 0.453 | 0.571 | - | - | 0.392 | 0.614 | 0.645 | - | 0.540 | - | 0.478 | 0.588 |
Sample | 1 | 2 | 3a | 3b | 4 | 5 | |||||||
Average (4 pts) | st dev | Average (4 pts) | st dev | Average (4 pts) | st dev | Average (5 pts) | st dev | Average (8 pts) | st dev | Average (5 pts) | st dev | ||
Li | 8546.20 | 463.86 | 7985.55 | 182.95 | 7859.06 | 75.06 | 7919.98 | 324.03 | 8899.59 | 1020.41 | 8073.58 | 322.46 | |
Be | 52.19 | 14.18 | 37.62 | 2.83 | 28.92 | 2.96 | 21.29 | 8.82 | 99.38 | 122.07 | 31.05 | 9.50 | |
Sc | 3.03 | 0.55 | 1.83 | 0.28 | 1.82 | 0.35 | 2.79 | 0.45 | 1.63 | 0.52 | 2.12 | 0.16 | |
V | 0.38 | 0.32 | 1.08 | 0.20 | 0.82 | 0.12 | 13.95 | 7.92 | 8.56 | 5.26 | 3.17 | 4.77 | |
Cu | 196.20 | 27.01 | 19.23 | 1.05 | 16.10 | 1.41 | 16.04 | 12.69 | 71.89 | 62.62 | 22.16 | 3.19 | |
Ga | 181.73 | 28.06 | 40.83 | 2.51 | 45.27 | 1.04 | 59.90 | 13.21 | 78.28 | 26.48 | 44.19 | 6.70 | |
Ge | 9.11 | 2.22 | 20.47 | 1.68 | 19.85 | 1.52 | 15.65 | 2.90 | 15.91 | 2.78 | 21.57 | 2.77 | |
Sr | 0.73 | 0.23 | 31.66 | 1.23 | 19.88 | 1.72 | 231.22 | 390.52 | 93.98 | 234.91 | 29.42 | 3.66 | |
Y | 0.25 | 0.17 | 0.46 | 0.05 | 0.35 | 0.03 | 0.24 | 0.15 | 0.22 | 0.08 | 0.39 | 0.20 | |
Ta | 4.63 | 3.57 | 1.07 | 0.14 | 0.28 | 0.01 | 0.56 | 0.31 | 3.18 | 5.43 | 0.44 | 0.40 | |
Pb | 11.94 | 4.76 | 43.78 | 2.22 | 35.05 | 1.19 | 2882.66 | 3775.66 | 184.51 | 453.38 | 163.22 | 71.23 | |
Th | 3.58 | 2.95 | 0.79 | 0.06 | 0.55 | 0.06 | 0.16 | 0.14 | 6.98 | 15.66 | 0.52 | 0.32 | |
U | 0.36 | 0.29 | 0.02 | 0.00 | bdl | 0.01 | 0.01 | 0.79 | 1.15 | 0.03 | |||
La | 44.13 | 18.50 | 24.29 | 1.46 | 13.58 | 0.35 | 22.86 | 14.36 | 9.50 | 4.54 | 17.07 | 4.19 | |
Ce | 46.68 | 19.98 | 49.72 | 3.99 | 30.16 | 0.30 | 48.87 | 26.13 | 15.89 | 8.20 | 37.41 | 11.14 | |
Pr | 2.35 | 1.08 | 5.13 | 0.38 | 2.87 | 0.10 | 4.94 | 2.44 | 1.44 | 0.85 | 3.60 | 1.08 | |
Nd | 3.05 | 1.40 | 14.54 | 1.49 | 7.46 | 0.24 | 13.43 | 6.78 | 3.42 | 2.55 | 9.15 | 2.88 | |
Sm | 0.53 | 0.36 | 3.14 | 0.69 | 1.96 | 0.17 | 2.74 | 1.23 | 1.17 | 0.41 | 2.29 | 0.95 | |
Eu | bdl | 0.12 | 0.03 | 0.12 | 0.04 | 0.13 | 0.05 | 0.05 | 0.02 | 0.10 | 0.04 | ||
Gd | 0.27 | 0.02 | 0.93 | 0.19 | 0.64 | 0.13 | 0.68 | 0.40 | 0.42 | 0.16 | 0.72 | 0.38 | |
Tb | 0.05 | 0.04 | 0.11 | 0.02 | 0.09 | 0.02 | 0.08 | 0.05 | 0.05 | 0.02 | 0.09 | 0.04 | |
Dy | 0.15 | 0.17 | 0.36 | 0.11 | 0.24 | 0.05 | 0.24 | 0.17 | 0.14 | 0.04 | 0.26 | 0.17 | |
Ho | bdl | bdl | 0.03 | 0.02 | 0.02 | 0.01 | 0.02 | 0.01 | 0.02 | 0.01 | |||
Er | 0.20 | 0.26 | bdl | 0.05 | 0.001 | bdl | 0.06 | 0.03 | bdl | ||||
Tm | bdl | 0.02 | 0.005 | 0.01 | 0.005 | 0.01 | 0.00 | bdl | bdl | ||||
Yb | 0.10 | 0.10 | bdl | bdl | 0.17 | 0.15 | bdl | ||||||
Lu | bdl | bdl | bdl | bdl | bdl | 0.01 | |||||||
Σ REE | 97.50 | 98.36 | 57.21 | 94.00 | 32.34 | 70.72 | |||||||
Sample | 6 | 9a | 9b | 10 | 11 | 12 | |||||||
Average (7 pts) | st dev | Average (3 pts) | st dev | Average (3 pts) | st dev | Average (8 pts) | st dev | Average (5 pts) | st dev | Average (4 pts) | st dev | ||
Li | 9993.23 | 1095.08 | 8494.71 | 249.68 | 8767.86 | 145.96 | 8444.96 | 1786.74 | 7175.63 | 2373.44 | 8271.11 | 399.03 | |
Be | 20.20 | 5.78 | 23.17 | 2.81 | 27.37 | 7.68 | 22.63 | 13.36 | 14.62 | 11.00 | 19.95 | 2.56 | |
Sc | 1.96 | 0.40 | 2.96 | 0.25 | 3.09 | 0.24 | 2.26 | 0.46 | 3.47 | 0.84 | 1.65 | 0.47 | |
V | 0.37 | 0.09 | 0.48 | 0.18 | 8.88 | 3.03 | 0.84 | 0.63 | 1.21 | 0.54 | 0.54 | 0.09 | |
Cu | 21.30 | 9.49 | 148.85 | 58.16 | 31.74 | 3.36 | 24.96 | 16.28 | 17.92 | 12.74 | 30.46 | 6.96 | |
Ga | 68.20 | 25.78 | 121.62 | 49.09 | 35.29 | 1.08 | 104.43 | 26.62 | 91.33 | 12.88 | 45.58 | 5.77 | |
Ge | 12.01 | 2.63 | 7.05 | 0.84 | 16.59 | 1.50 | 6.97 | 2.13 | 7.10 | 1.54 | 11.74 | 3.80 | |
Sr | 104.28 | 95.41 | 4.37 | 1.46 | 168.96 | 25.82 | 30.01 | 25.73 | 175.48 | 356.03 | 16.88 | 4.55 | |
Y | 0.36 | 0.05 | 0.46 | 0.08 | 0.48 | 0.20 | 0.65 | 0.62 | 0.31 | 0.11 | 0.21 | 0.12 | |
Ta | 1.11 | 0.36 | 1.06 | 0.39 | 1.02 | 0.43 | 1.04 | 1.47 | 0.16 | 0.10 | 0.56 | 0.25 | |
Pb | 135.44 | 129.63 | 13.36 | 1.50 | 64.72 | 10.31 | 40.34 | 60.43 | 881.33 | 710.51 | 27.57 | 6.20 | |
Th | 0.23 | 0.09 | 1.07 | 0.40 | 0.49 | 0.16 | 1.55 | 1.67 | 0.52 | 0.25 | 0.32 | 0.12 | |
U | 0.03 | 0.02 | 0.06 | 0.01 | bdl | 0.06 | 0.02 | 0.06 | 0.06 | 0.02 | 0.02 | ||
La | 22.46 | 4.14 | 23.09 | 7.25 | 33.99 | 10.92 | 18.37 | 19.28 | 9.75 | 8.73 | 14.74 | 5.05 | |
Ce | 46.61 | 14.32 | 49.63 | 12.21 | 66.11 | 21.77 | 35.44 | 44.29 | 20.35 | 18.36 | 31.63 | 11.11 | |
Pr | 4.65 | 1.67 | 4.84 | 0.58 | 6.41 | 2.04 | 3.98 | 5.18 | 2.03 | 1.80 | 3.15 | 1.06 | |
Nd | 12.45 | 5.70 | 11.78 | 0.79 | 18.64 | 5.80 | 13.82 | 16.80 | 7.01 | 4.65 | 8.26 | 2.74 | |
Sm | 2.83 | 1.40 | 3.86 | 0.57 | 3.76 | 1.18 | 4.74 | 5.45 | 1.73 | 1.19 | 1.91 | 0.70 | |
Eu | 0.13 | 0.05 | 0.07 | 0.03 | 0.32 | 0.05 | 0.13 | 0.16 | 0.11 | 0.03 | 0.09 | 0.02 | |
Gd | 0.84 | 0.44 | 1.31 | 0.35 | 1.49 | 0.59 | 1.66 | 1.44 | 0.50 | 0.38 | 0.49 | 0.16 | |
Tb | 0.08 | 0.02 | 0.15 | 0.02 | 0.17 | 0.02 | 0.21 | 0.18 | 0.07 | 0.05 | 0.07 | 0.03 | |
Dy | 0.24 | 0.12 | 0.48 | 0.17 | 0.41 | 0.14 | 0.61 | 0.61 | 0.21 | 0.10 | 0.16 | 0.05 | |
Ho | bdl | 0.02 | 0.01 | 0.04 | 0.02 | 0.06 | 0.04 | 0.03 | 0.03 | bdl | |||
Er | 0.05 | 0.03 | 0.05 | 0.04 | 0.07 | 0.03 | bdl | 0.05 | 0.02 | 0.08 | 0.04 | ||
Tm | 0.01 | 0.01 | 0.02 | 0.01 | bdl | 0.03 | 0.01 | 0.02 | bdl | bdl | |||
Yb | bdl | bdl | bdl | bdl | 0.15 | 0.20 | 0.10 | 0.01 | |||||
Lu | 0.02 | 0.01 | bdl | bdl | 0.02 | 0.01 | 0.04 | 0.05 | bdl | ||||
Σ REE | 90.37 | 95.29 | 131.42 | 79.06 | 42.06 | 60.67 |
Sample | 1 | 2 | 12 |
---|---|---|---|
Temperature | 293(2) K | 293(2) K | 293(2) K |
Wavelength | 0.71073 Å | 0.71073 Å | 0.71073 Å |
Crystal system | Trigonal | Trigonal | Trigonal |
Space group | R3m | R3m | R3m |
Unit cell dimensions | a = 15.8283(3) Å | a = 15.8951(8) Å | a = 15.8909(2) Å |
c = 7.09392(18) Å | c = 7.1216(4) Å | c = 7.1163(3) Å | |
Volume | 1539.16(5) Å3 | 1558.22(15) Å3 | 1556.26(7) Å3 |
Z | 3 | 3 | 3 |
Absorption coefficient | 1.004 mm−1 | 1.056 mm−1 | 1.020 mm−1 |
F(000) | 1395 | 1430 | 1422 |
Crystal size (mm3) | 0.29 × 0.61 × 0.47 | 0.35 × 0.51 × 0.65 | 0.40 × 0.53 × 0.70 |
θ range for data collection | 3.23 to 36.11°. | 3.22 to 29.04°. | 3.22 to 35.95°. |
Index ranges | −26 ≤ h ≤ 26, | −16 ≤ h ≤ 13, | −25 ≤ h ≤ 26, |
−24 ≤ k ≤ 24, | −20 ≤ k ≤ 20, | −25 ≤ k ≤ 25, | |
−9 ≤ l ≤ 9 | −9 ≤ l ≤ 9 | −9 ≤ l ≤ 9 | |
Reflections collected | 14,418 | 3806 | 14,500 |
Independent reflections | 1571 | 914 | 1261 |
R(int) | 0.0277 | 0.0216 | 0.0334 |
Completeness to θ = 35.95° | 89.30% | 95.20% | 72.70% |
Refinement method | Full-matrix least-squares on F2 | Full-matrix least-squares on F2 | Full-matrix least-squares on F2 |
Data/restraints/parameters | 1571/1/97 | 914/1/97 | 1261/1/97 |
Goodness-of-fit on F2 | 1.161 | 1.076 | 1.09 |
Final R indices [I > 2σ (I)] | R1 = 0.0159 | R1 = 0.0175 | R1 = 0.0179 |
wR2 = 0.0400 | wR2 = 0.0452 | wR2 = 0.0448 | |
R indices (all data) | R1 = 0.0168 | R1 = 0.0177 | R1 = 0.0186 |
wR2 = 0.0403 | wR2 = 0.0453 | wR2 = 0.0451 | |
Absolute structure parameter | 0.04(7) | 0.01(11) | −0.10(10) |
Extinction coefficient | 0.0049(3) | 0.0041(3) | 0.0024(2) |
Largest diff. peak and hole | 0.461 and | 0.530 and | 0.889 and |
−0.439 e.Å−3 | −0.497 e.Å−3 | −0.709 e.Å−3 |
Sample | 1 | 2 | 12 |
---|---|---|---|
T–O(6) | 1.6092(9) | 1.6049(15) | 1.6021(14) |
T–O(7) | 1.6103(7) | 1.6134(13) | 1.6110(10) |
T–O(4) | 1.6208(5) | 1.6263(8) | 1.6260(7) |
T–O(5) | 1.6363(5) | 1.6412(9) | 1.6389(8) |
<T–O> | 1.619 | 1.621 | 1.62 |
V (Å3) | 2.173 | 2.181 | 2.173 |
TQE | 1.0017 | 1.0023 | 1.0022 |
TAV | 6.812 | 9.502 | 9.0511 |
B–O(2) | 1.3630(18) | 1.352(4) | 1.361(3) |
B–O(8) (×2) | 1.3798(10) | 1.386(2) | 1.3850(15) |
<B–O> | 1.374 | 1.375 | 1.377 |
X–O(2) (×3) | 2.4570(18) | 2.426(3) | 2.425(2) |
X–O(5) (×3) | 2.7422(13) | 2.748(2) | 2.7492(17) |
X–O(4) (×3) | 2.8095(13) | 2.810(2) | 2.8078(18) |
<X–O> | 2.67 | 2.661 | 2.661 |
V (Å3) | 31.14 | 31.419 | 31.086 |
Y–O(2) (×2) | 1.9620(9) | 1.9824(15) | 1.9812(14) |
Y–O(6) (×2) | 1.9591(9) | 2.0150(15) | 2.0129(13) |
Y–O(1) | 1.9577(14) | 2.028(2) | 2.024(2) |
Y–O(3) | 2.1346(14) | 2.171(2) | 2.1678(19) |
<Y–O> | 1.989 | 2.032 | 2.03 |
V (Å3) | 10.125 | 10.796 | 10.759 |
OQE | 1.0252 | 1.0253 | 1.0253 |
OAV | 79.39 | 79.54 | 79.7 |
Z–O(6) | 1.8643(8) | 1.8506(15) | 1.8514(12) |
Z–O(7) | 1.8816(8) | 1.8823(14) | 1.8834(12) |
Z–O(8) | 1.8877(8) | 1.8865(14) | 1.8847(11) |
Z–O(8) | 1.9008(8) | 1.9114(14) | 1.9098(11) |
Z–O(7) | 1.9415(7) | 1.9551(14) | 1.9551(11) |
Z–O(3) | 1.9647(6) | 1.9617(11) | 1.9612(10) |
<Z–O> | 1.907 | 1.908 | 1.908 |
V (Å3) | 9.039 | 9.079 | 9.075 |
OQE | 1.0154 | 1.0137 | 1.0137 |
OAV | 52.08 | 45.82 | 45.75 |
O(3) –H(3) | 0.80(3) | 0.71(4) | 0.72(4) |
Site | (Electrons Per Site, eps) for Tourmalines 1, 2, 12 | ||
---|---|---|---|
1 | 2 | 12 | |
X (obs) | 8.73 | 12.43 | 11.81 |
X (calc) | 7.95 | 11.34 | 10.61 |
Y (obs) | 9.49 | 11.98 | 11.26 |
Y (calc) | 9.25 | 11.97 | 11.12 |
Z (obs) | 12.96 | 12.83 | 12.85 |
Z (calc) | 13 | 13 | 13 |
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Diella, V.; Pezzotta, F.; Bocchio, R.; Marinoni, N.; Cámara, F.; Langone, A.; Adamo, I.; Lanzafame, G. Gem-Quality Tourmaline from LCT Pegmatite in Adamello Massif, Central Southern Alps, Italy: An Investigation of Its Mineralogy, Crystallography and 3D Inclusions. Minerals 2018, 8, 593. https://doi.org/10.3390/min8120593
Diella V, Pezzotta F, Bocchio R, Marinoni N, Cámara F, Langone A, Adamo I, Lanzafame G. Gem-Quality Tourmaline from LCT Pegmatite in Adamello Massif, Central Southern Alps, Italy: An Investigation of Its Mineralogy, Crystallography and 3D Inclusions. Minerals. 2018; 8(12):593. https://doi.org/10.3390/min8120593
Chicago/Turabian StyleDiella, Valeria, Federico Pezzotta, Rosangela Bocchio, Nicoletta Marinoni, Fernando Cámara, Antonio Langone, Ilaria Adamo, and Gabriele Lanzafame. 2018. "Gem-Quality Tourmaline from LCT Pegmatite in Adamello Massif, Central Southern Alps, Italy: An Investigation of Its Mineralogy, Crystallography and 3D Inclusions" Minerals 8, no. 12: 593. https://doi.org/10.3390/min8120593
APA StyleDiella, V., Pezzotta, F., Bocchio, R., Marinoni, N., Cámara, F., Langone, A., Adamo, I., & Lanzafame, G. (2018). Gem-Quality Tourmaline from LCT Pegmatite in Adamello Massif, Central Southern Alps, Italy: An Investigation of Its Mineralogy, Crystallography and 3D Inclusions. Minerals, 8(12), 593. https://doi.org/10.3390/min8120593