NEW DATA ABOUT THE LAHÓCA HIGH SULFIDA- TION MINERALIZATION János Földessy, Éva Hartai, László Kupi University of Miskolc Institute ofMineralogy and Geology foldshe@gold. uni-miskolc.hu Abstract: The Lahóca high sulfidation mineralization is structurally controlled by NW-SE and N-S striking tectonic zones. The central brecciated zone contains the major part of the mineralization with its upper boundary contact ,'Bluestone“(clayeyl altered rock). The deeper continuation of the brecciated zones as possible feeder dikes can be traced south, west and beneath the Lejtakna pipe breccia. The mineralization displays the character of the outward zoning of advanced argillic altera tion. The main Cu-bearing minerals are enargite and luzonite. Gold occurs in native form of high fineness forming either fine coating on pyrite crystals or form individual grains in the silica matrix. According to the radiometric data, the whole Oligocene period was associated by active ore forming hydrothermal activities near the Lahóca volcanic centre. 1. INTRODUCTION The Lahoca has long been known for its copper mineralization associated by small amount of silver and gold. A small underground mine worked in the copper ore-bodies from 1850s until 1979. Gold potential of the locality has gained im portance in the late 1980s. Subsequent ore explorations (about 10,000 m drilling) defined significant resources in the 1994-1997 period. Resource estimate of this gold ore resource is 46 metric tons of gold at 0.5 g/t cut-off grade. The average thickness of the ore zone is 30 m with a rich high- grade center of more than 100 m vertical thickness of 1.77 mg/kg of average gold content. The average silver content is low, but at certain samples of the deposit it reaches 0.1 %. This article reviews the new geological findings discovered during and after the 1993-1997 exploration program. 2. ORE MINERALIZATIONS RELATED TO PALAEOGENE VOLCA- NICS IN THE CARPATHIANS Near-surface Paleogene ore mineralization related to intermediate igneous rocks occurs in two places in Carpathian Belt: at Lahóca, and at the eastern part 129