The Wafi River High Sulphur Epithermal Gold Deposit, Papua New Guinea

The Waft River gold deposit is hosted by low grade metasediments which have been intruded by a dacite/andesite porphyry complex. Wafi River is classified as a high sulphur, epithermal type gold deposit having: a high sulphur content, a close association with calc-alkalic igneous rocks, zoned advanced argillic and argillic alteration, and enargite group minerals. Gold occurs as minute inclusions in pyrite and pyrrhotite within intermediate dickite/kaohnite - interlayered illitic clay alteration zones. Central leached silicic, alunite and pyrophyllite zones and peripheral chloritic zones are low in gold. The gold mineralisation at Wafi is interpreted to have been predominantly caused by mixing of hot upwelling acidic magmatic mineralised fluids with cool, neutral meteoric/hydrothermal fluids within permeable sediments. Locallised high grade breccia zones are encountered within the porphyry. An initial resource in excess of I million ounces Au has been defined.