Semi (caesium geyserites)
Southern Tibet (Xizang), Shiquanhe-Yarlung Zangbo geothermal field, China
OtherCs (Rb, Li, B)
- Type
- Hot-spring caesium geyserites
Caesium deposit in geyserites (siliceous sinters) of rare-alkali-rich geothermal springs along the Indus-Yarlung Zangbo suture; about 15,000 t Cs for the region (Zhang, 2014). Li et al. (2023): rare alkali enrichment by metapelite melting then water-rock interaction at 210-250 °C in the reservoir, and Cs adsorption during silica precipitation; loss of Cs and B during the opal-A, opal-CT, chalcedony, quartz transformation. Coordinates not published. Older geyserites rich in quartz and kaolinite, mean Cs 40 µg/g; Na-Cl springs at 76 to 84 °C; nearby Himalayan tourmaline leucogranite (Be-Nb-Ta).
δ11B in ‰ (per mil) Values of the same system
Standard : NIST SRM 951
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| −6.2 ± 0.6 ‰ | −6.6 / −5.8 ‰ | 2 | older quartz geyserite Mean and standard deviation recalculated from 2 analyses, -6.6 to -5.8 (SM-29 -6.6; SM-37 -5.8). 448.9 and 75.6 µg/g B. | Li et al. (2023), Boron isotope constraints on the migration and accumulation of rare alk… |
| −6.8 ± 1 ‰ | −7.9 / −6.2 ‰ | 3 | recent quartz veins Mean and standard deviation recalculated from 3 analyses, -7.9 to -6.2 (SM-32 -7.9; SM-33 -6.2; SM-45 -6.3). 503 to 605 µg/g B, rich in rare alkalis; outside the -6.6 to -0.4 ‰ range given for Semi in the text. | Li et al. (2023), Boron isotope constraints on the migration and accumulation of rare alk… |
| −3.5 ± 2.7 ‰ | −5.4 / −0.4 ‰ | 3 | alteration products (kaolinite, quartz-calcite clusters) Mean and standard deviation recalculated from 3 analyses, -5.4 to -0.4 (SM-9 amas de quartz et calcite -5.4; SM-13 kaolinite à plagioclase et quartz -4.7; SM-34 kaolinite -0.4). 92.7 to 175.5 µg/g B. | Li et al. (2023), Boron isotope constraints on the migration and accumulation of rare alk… |
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). Semi (caesium geyserites), isotope signatures. https://www.isofind.tech/isotopes/en/deposits/semi-geyserites-a-cesium/ (accessed 2026-10-19).
@misc{isofind2026semicaesiumgeyseritesisotopes,
title = {Semi (caesium geyserites), isotope signatures},
author = {{IsoFind Atlas}},
year = {2026},
url = {https://www.isofind.tech/isotopes/en/deposits/semi-geyserites-a-cesium/},
note = {Accessed 2026-10-19}
}Updated : 2026-10-19