TYPOMORPHIC SIGNS OF PLACER GOLD OF THE LEFT ULAKHAN HAPTASYNNAAKH RIVER (ANABAR SHIELD)

Typomorphic signs of placer gold of the Left Ulakhan Haptasynnaakh river, draining rocks of the central part of the Billyakh tectonofluid zone of the Anabar shield have been studied, in order to identify its possible primary sources. The predominance in the placer of gold of ore-habit and poorly rounded angular-cloddy grains with an unrounded micropitted-tubercular surface often with adhesions of variable aluminosilicate composition and relics of small growths of quartz and potassium feldspar, as well as the fraction proportion >0.5 mm to 40% allowed us to refer the studied gold to a autochtonous metal. The study of the nearby sulfidized rocks of the Haptasynnakh zone showed that ore mineralization is represented by a variety of mineral forms. Pyrite is the main ore mineral. A wide range of telluride minerals has been identified, icluding predominating silver and bismuth tellurides. For the first time, lamellar and rod-shaped gold was identified from the crushed samples of mineralized rocks. Similar composition of mineral inclusions in placer gold of the Left Ulakhan Haptasynnakh river and mineral parageneses of ores of the Haptasynnakh ore zone allows us to assert that the ore occurrences of the zone are the primary sources of the studied gold. The discovery of gold of an ore habit of a fraction >0.5 mm in the placer indicates formation of a relatively large noble metal in deeper horizons of mineralization, than identified gold at this stage of research, that determines the positive prospects for further study of the Haptasynnakh ore zone.