Petrographic and mineralogical study of the Kilmacoo gold occurrence, Avoca District, Southeast Ireland

• Petrographic investigation of the quartz vein hosted Kilmacoo gold occurrence spatially associated with the copper rich Avoca massive sulphide ore body evidenced a close association between gold and sulphides. Visible electrum grains are frequently observed within chalcopyrite, and more rarely as minute inclusions in both arsenopyrite and pyrite. Mineralogical investigations also revealed complex sulphide paragenetic succession from framboidal pyrite to colloform and idiomorphic cements with overall a low arsenopyrite content. We also documented the presence of hydrothermal phosphates (apatite and monazite) subsequently altered in aluminum phosphate sulphate minerals, as well as a broad diversity of phyllosilicates. These observations as well as the cross cutting relationships tend to indicate a brittle deformation event involving possible remobilization of some of the copper mineralization from the main VMS ore body. At the present time the source of gold is still under investigation to determine the possible contribution from both local and distal sources.

Subject headings

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Geologi (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Geology (hsv//eng)

Keyword

Ore Geology

Malmgeologi

Publication and Content Type

ref (subject category)

kon (subject category)