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Mineralium Deposita

, Volume 30, Issue 3–4, pp 323–327 | Cite as

Occurrences of dendritic gold at the McLaughlin Mine hot-spring gold deposit

  • R. L. Sherlock
  • N. J. Lehrman
Mineral Deposit Letters

Abstract

Two styles of gold dendrites are variably developed at the McLaughlin Mine. The most abundant occurrence is hosted by amber-coloured hydrocarbon-rich opal. Silica likely precipitated from a boiling hydrothermal fluid and complexed with immiscible hydrocarbons forming an amorphous hydrocarbon-silica phase. This phase likely scavenged particulate gold by electrostatic attraction to the hydrocarbon-silica phase. The dendritic nature of the gold is secondary and is the result of dewatering of the amorphous hydrocarbon-silica phase and crystallization of gold into syneresis fractures. The second style of dendritic gold is hosted within vein swarms that focused large volumes of fluid flow. The dendrites occur along with hydrocarbon-rich silica at the upper contact of the vein margins which isolated the dendrites allowing sufficient time for them to grow. In a manner similar to the amber-coloured opal, the dendrites may have formed by scavenging particulate gold by electrostatic attraction to the hydrocarbon-silica phase.

Keywords

Gold Crystallization Hydrocarbon Boiling Fluid Flow 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag 1995

Authors and Affiliations

  • R. L. Sherlock
    • 1
  • N. J. Lehrman
    • 2
  1. 1.Mineral Deposit Research Unit, Department of Geological SciencesUniversity of British ColumbiaVancouver
  2. 2.Homestake Mining CompanySparks

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