Abstract
The polymetallic Huanuni deposit, a world-class tin deposit, is part of the Bolivian tin belt. As a likely case for a “mesothermal” or transitional deposit between epithermal and porphyry Sn types (or shallow porphyry Sn), it represents a case that contributes significantly to the systematic study of the distribution of critical elements within the “family” of Bolivian tin deposits. In addition to Sn, Zn and Ag, further economic interest in the area resides in its potential in critical elements such as In, Ga and Ge. This paper provides the first systematic characterisation of the complex mineralogy and mineral chemistry of the Huanuni deposit with the twofold aim of identifying the mineral carriers of critical elements and endeavouring plausible metallogenic processes for the formation of this deposit, by means of a multi-methodological approach. With In concentrations consistently over 2000 ppm, the highest potential for relevant concentrations in this metal resides in widespread tin minerals (cassiterite and stannite) and sphalerite. Hypogene alteration assemblages are hardly developed due to the metasedimentary nature of host rocks, but the occurrence of potassium feldspar, schorl, pyrophyllite and dickite as vein material stand for potassic to phyllic or advanced argillic alteration assemblages and relatively high-temperature (and low pH) mineralising fluids. District-scale mineralogical zonation suggests a thermal zonation with decreasing temperatures from the central to the peripheral areas. A district-scale zonation has been also determined for δ34SVCDT values, which range −7.2‰ to 0.2‰ (mostly −7‰ to −5‰) in the central area and −4.2‰ to 1.0‰ (mainly constrained between −2‰ and 1‰) in peripheral areas. Such values stand for magmatic and metasedimentary sources for sulfur, and their spatial zoning may be related to differential reactivity between mineralising fluids and host rocks, outwardly decreasing from the central to the peripheral areas.
Highlights
The Huanuni Sn–W–Pb–Ag–Zn deposit is the largest tin producer in Bolivia and, alongside theSan Rafael deposit in Peru, spearheads the tin production in the world
The available data from fluid inclusions in this deposit indicate the occurrence of saline brines up to 26 wt.% NaCl equiv., homogenisation temperatures up to 425 ◦ C, and many metals dissolved in inclusion fluids, including Sn and Ge [15,17,31]
Their research included repeated LA-ICP-MS analysis of a PS-1 and obtained values comparable (
Summary
The Huanuni Sn–W–Pb–Ag–Zn deposit is the largest tin producer in Bolivia and, alongside the. Increasing international demand is envisaged for In, Ge and Ga, in emerging technologies such as the production of photovoltaic cells (In and Ga), optical fibre and infrared optical technologies (Ge) These metals are listed as Critical Raw Materials for the European Union [11], which attests to their strategic importance due to the large share in their supply by China—By far, the largest global producer of In, Ga and Ge. The Andean cordillera contains four metallogenic belts from west to east, these are the Fe, porphyry. The present study aims at the determination of the distribution of critical metals in the Huanuni deposit in the light of the time and space distribution of the minerals that bear them This includes the determination of its paragenetic sequence and differences in the mineralogy of central to distal portions of the deposit. Showing thethe location of the study areaarea (Huanuni deposit: whitewhite box)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
