Characterization of Gold of the Murcielago Fluvial Placer (Central Honduras) and Its Possible Primary Sources

• Published in: Geosciences (Basel) Vol. 13; no. 6; p. 175
• Main Authors: Nazzareni, Sabrina, Alunno, Simona, Zaccarini, Federica, Mattioli, Michele, Murroni, Alessandro, Michele, Alessandro Di, Renzulli, Alberto
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01-06-2023
• Subjects: Analysis; Arsenopyrite; Calcite; Cassiterite; Central America; Chemistry; Composition; Creeks & streams; Earth science; electron microprobe; Environmental aspects; Geomorphology; Gold; gold deposit; gold grains; Grains; Haematite; Hematite; Ilmenite; Inclusions; lode gold; Magnetite; Metamorphic rocks; Micas; Mine surveying; Mineralization; Mineralogy; Mines and mineral resources; Morphology; placer; Pyrite; Quartz; Rutile; Sediments; Silicates; Sphalerite; Tourmaline; Zincblende; Zircon; Honduras; Central America
• DOI: 10.3390/geosciences13060175
• EISSN: 2076-3263

The Murcielago gold placer is located in the Lepaguare Valley, Olancho Department (Central Honduras). The placer mineralogy includes silicates (quartz, garnets, amphibole, Ca-pyroxene, micas, epidote, and tourmaline); calcite; and in the heavy fraction, zircon, ilmenite–rutile, magnetite, hematite, cassiterite, and cinnabar. Gold grains recovered from the Murcielago placer production plant are mainly flattened grains with a moderately to high elliptical shape. The composition of the gold grains varies continuously in the range Au46Ag54 to Au88Ag12. Few of them are characterized by Au-rich rims of a few microns in size (Ag 3-1 atoms percent (at%)). Gold from the Canan lode deposit, a nearby hydrothermal Au mineralization area, has a composition (from Au54Ag44 to Au81Ag19) overlapping the composition of the Murcielago grains. Inclusions in the alluvial gold particles are arsenopyrite, pyrite, acanthite, sphalerite, and hematite. On the basis of the placer mineralogy and the gold grains analyses, possible gold source(s) include the Canan lode and skarn gold deposits in the area. We obtained new data on the Murcielago gold placer that will be the basis for an exploration of the potential sources of gold in the area.