Los Trancos (bentonite)
Almería, Cabo de Gata, Spain
Otherbentonite
- Type
- Bentonite (Mg, Ca)
Smectite bentonite deposit. Mainly marine deposition: proximal marine volcano-sedimentary setting, parent material rhyolitic tuff; hydrothermal, 40 to 100 °C alteration; Langhian to Messinian (15 to 7 Ma). Köster et al. (2019): δ11B of purified smectites and fluid δ11B calculated for trigonal or tetrahedral boron at 25 and 90 °C.
δ11B in ‰ (per mil) Values of the same system
Standard : NIST SRM 951
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| 7.1 ± 0.5 ‰ | 6.2 / 8 ‰ | smectite (< 0.2 µm) treated with mannitol Single sample, published mean and 2SD (uncertainty halved to 1σ): TR-M +7.1 (2SD 1.0, +6.2 to +8.0, 17.6 µg/g B). | Köster et al. (2019), The boron isotope geochemistry of smectites from sodium, magnesium … | |
| 12.2 ± 0.45 ‰ | 11.7 / 12.9 ‰ | smectite (< 0.2 µm) treated with mannitol and ammonium-exchanged, structural boron Single sample, published mean and 2SD (uncertainty halved to 1σ): TR-A +12.2 (2SD 0.9, +11.7 to +12.9, 23.7 µg/g B). | Köster et al. (2019), The boron isotope geochemistry of smectites from sodium, magnesium … |
Deposits of the same type
- Central African Copperbelt (whole province) DR Congo and Zambia
- Witwatersrand basin South Africa
- Stelvio Italy
- Oris Italy
- Kupferschiefer, Lubin-Sieroszowice district Poland
- Timna Israël
- Datangpo-type manganese (Gaolou, Minle, Zhenxing) China
- Eyller Bruch bog iron ore Germany
Cite this page
IsoFind Atlas (2026). Los Trancos (bentonite), isotope signatures. https://www.isofind.tech/isotopes/en/deposits/los-trancos-bentonite/ (accessed 2026-10-20).
@misc{isofind2026lostrancosbentoniteisotopesig,
title = {Los Trancos (bentonite), isotope signatures},
author = {{IsoFind Atlas}},
year = {2026},
url = {https://www.isofind.tech/isotopes/en/deposits/los-trancos-bentonite/},
note = {Accessed 2026-10-20}
}Updated : 2026-10-20