Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Morphological characterization of lode gold in the auriferous quartz veins at M’Popo mine, Angola, by computed tomography and optical microscopy

Morphological characterization of lode gold in the auriferous quartz veins at M’Popo mine,... Auriferous vein samples of the Angolan M’Popo deposit were characterized by a combination of 2D microscopy and 3D computed tomography (CT) in order to visualize and assess the gold distribution and gold morphology in in situ high-grade gold ore. The 0.1–2.4 m wide hydrothermal quartz veins in the Mesoproterozoic M’Popo granitic complex are composed mainly of quartz and pyrite, minor other sulfides and (visible) gold. The favourable X-ray attenuation/density contrast within this mineral assemblage allows delineation of the gold particle fraction so that gold particles of <0.01–19.95 mm³ in volume have been identified. Statistical analysis reveals that the bulk (∼99.98%) of all gold particles belong to the smallest volume classes (≤0.02 mm²) while large particles (>0.5 mm³) are few. The contrast between rounded, compact smaller particles and branched larger ones is clearly expressed in the CT reconstructions while transitions between these reflect a likely continuum in gold mineralization. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Applied Earth Science Taylor & Francis

Morphological characterization of lode gold in the auriferous quartz veins at M’Popo mine, Angola, by computed tomography and optical microscopy

Download PDF
25 pages

Morphological characterization of lode gold in the auriferous quartz veins at M’Popo mine, Angola, by computed tomography and optical microscopy

Abstract

Auriferous vein samples of the Angolan M’Popo deposit were characterized by a combination of 2D microscopy and 3D computed tomography (CT) in order to visualize and assess the gold distribution and gold morphology in in situ high-grade gold ore. The 0.1–2.4 m wide hydrothermal quartz veins in the Mesoproterozoic M’Popo granitic complex are composed mainly of quartz and pyrite, minor other sulfides and (visible) gold. The favourable X-ray attenuation/density contrast...
Loading next page...
 
/lp/taylor-francis/morphological-characterization-of-lode-gold-in-the-auriferous-quartz-GoaaVYO852
Publisher
Taylor & Francis
Copyright
© 2023 Institute of Materials, Minerals and Mining and The AusIMM
ISSN
2572-6838
eISSN
2572-6846
DOI
10.1080/25726838.2023.2219116
Publisher site
See Article on Publisher Site

Abstract

Auriferous vein samples of the Angolan M’Popo deposit were characterized by a combination of 2D microscopy and 3D computed tomography (CT) in order to visualize and assess the gold distribution and gold morphology in in situ high-grade gold ore. The 0.1–2.4 m wide hydrothermal quartz veins in the Mesoproterozoic M’Popo granitic complex are composed mainly of quartz and pyrite, minor other sulfides and (visible) gold. The favourable X-ray attenuation/density contrast within this mineral assemblage allows delineation of the gold particle fraction so that gold particles of <0.01–19.95 mm³ in volume have been identified. Statistical analysis reveals that the bulk (∼99.98%) of all gold particles belong to the smallest volume classes (≤0.02 mm²) while large particles (>0.5 mm³) are few. The contrast between rounded, compact smaller particles and branched larger ones is clearly expressed in the CT reconstructions while transitions between these reflect a likely continuum in gold mineralization.

Journal

Applied Earth Science – Taylor & Francis

Published: Apr 3, 2023

Keywords: M’Popo mine; computed tomography; lode gold mineralization; Angola

References

  • An introduction to the application of X-ray microtomography to the three-dimensional study of igneous rocks
  • Uncloaking invisible gold: Use of Nanosims to evaluate gold, trace elements, and sulfur isotopes in pyrite from Carlin-type gold deposits
  • Gold exploration in two and three dimensions: improved and correlative insights from microscopy and X-ray computed tomography
  • High-resolution X-ray computed tomography in geosciences: A review of the current technology and applications
  • Concentration of “invisible gold” in the common sulfides
  • Geochronological review of the Precambrian in western Angola: links with Brazil
  • Characterisation of gold ores by X-ray computed tomography – part 2: applications to the determination of gold particles size and distribution. Extended abstracts
  • Determination of the sampling liberation diameter in a high-grade coarse gold ore by high-resolution X-ray computed tomography
  • 3D spatial distribution of ore mineral phases using high resolution synchrotron micro-computed tomography (μCT) combined with optical microscopy
  • Investigation of LPBF A800H steel parts using computed tomography and Mössbauer spectroscopy
  • Computed tomography of gold ore from the progera mine, Papua New Guinea: implications for acid rock drainage prediction
  • X-ray computer tomography investigations on solid-state lithium-ion battery system
  • High-resolution X-ray computed tomography and its application to ore deposits: from data acquisition to quantitative three-dimensional measurements with case studies from Ni-Cu-PGE deposits
  • X-ray microcomputed tomography (μCT) for mineral characterization: a review of data analysis methods
  • Proterozoic geochronology and tectonic evolution of Southern Africa
  • The occurrence, mining and recovery of diamonds. Journal of the Chemical
  • Characterisation of gold ores by X-ray computed tomography – part 1: software for calibration and quantification of mineralogical phases. extended abstracts; Sep 5–7
  • The mineral industry of Angola, Mozambique, and Guinea Bissau
  • The relationship between placer gold particle shape, rimming, and distance of fluvial transport as exemplified by gold from the Klondike district, Yukon Territory, Canada
  • Application of high-resolution X-ray computed tomography to mineral deposit origin, evaluation, and processing
  • The quantitative analysis of tungsten ore using X-ray microCT: case study
  • Nearshore marine garnet and magnetite placers in the Erongo and S-Kunene regions
  • Making war and lots of money: The political economy of protracted conflict in Angola
  • Quantification of the morphology of gold grains in 3D using X-ray microscopy and SEM photogrammetry
  • Multi-method 2D and 3D reconstruction of gold grains morphology in alluvial deposits: a review and application to the Riviére du Moulin (Québec, Canada)
  • Quantitative 3D shape descriptor of gold grains from quaternary sediments: application to mineral exploration in glaciated terrain, Amaruq orogenic gold deposit (Nunavut, Canada)
  • New U-Pb SHRIMP ages from the Lubango region, SW Angola: insights into the paleoproterozoic evolution of the Angolan shield, southern Congo craton, Africa
  • Diamond exploration and mining in Southern Africa: some thoughts on past, current, and possible future trends
  • An overview of the geology and major ore deposits of Central Africa: explanatory note for the 1:4,000,000 map “geology and major ore deposits of Central Africa”
  • Invisible gold and tellurium in arsenic-rich pyrite from the emperor gold deposit, Fiji: implications for gold distribution and deposition
  • Calibrated X-ray micro-tomography for mineral ore quantification
  • Recording the largest gabbro-anorthosite complex worldwide: the Kunene complex (KC), SW Angola
  • M’Popo deposit, a granite-hosted gold vein system in the MesoProterozoic of SE Angola
  • Gold grain morphology and composition as an exploration tool: application to gold exploration in covered areas
  • Angola – the mineral industry in 1970
  • Focused ion beam (FIB) combined with SEM and TEM: advanced analytical tools for studies of chemical composition, microstructure and crystal structure in geomaterials on a nanometre scale
  • Variation in placer style, gold morphology, and gold particle behavior down gravel bed-load rivers: An example from the Shotover/Arrow-Kawarau-Clutha river system, Otago, New Zealand