CHARACTERISTIC OF GOLD MINERALISATION BASED ON VEIN TEXTURE OF QUARTZ AND GRADE ORE IN VEIN PKR-02, MOUNT PONGKOR, BOGOR, WEST JAVA

• Main Author: Adiyasari, Mutiara
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/70160
• Institution: Institut Teknologi Bandung

Low sulfide epithermal deposits on Mount Pongkor is one of the mining areas with silver and gold commodities in West Java. There are four main veins, namely PKR-01, PKR-02, PKR-03, and PKR-04. The study was conducted on the texture of the veins that develop in PKR-02 veins are divided into three blocks, namely the south block, central block, and north block. It can be used to determine mineralization characteristics and ore shoot potential in further exploration activities. The process of data collection is done by mapping the details of subsurface geology, as well as descriptions at ten drill points to review geology, alteration, texture variation, and mineralization. As well as secondary data collection in the form of elemental geochemical data in the form of fire assay to determine the levels of precious metal at ten drill points and five detailed mapping of subsurface geology on active fronts. Analysis of thin section, polishing section, and analysis of quartz vein samples megascopically to determine the alteration and mineralization In general, there are three main rock units found in the study area, consisting of accretion Tuff lapilli, Tuff breccia, and Tuff lapilli units that are Miocene in age, with geological structures dominated by horizontal fault conjugate structures directed towards NW-SE and NNE-SSW which affects the mineralization process, is thought to be of tertiary age (Late Miocene – Pliocene). There are four mineralized urate facies, namely CQ facies (Carbonate Quartz), MOQ facies (Manganese Oxide Quartz), BOQ facies (banded Opaline Quartz), and GSQ facies (Grey Sulphide Quartz), and one unmineralized urate facies, namely LGQ facies (Late Goedic Quartz) in the study area. In PKR-02 veins south block and north block are dominated by crustiform texture, colloform, and breccia veins, with the dominance of facies in the form of facies BOQ and facies GSQ so that it has the potential ore shoot 2-60 ppm Au. The middle block is dominated by Breccia, chalcedony, and saccharoidal-crystalline with a dominance of CQ facies, MOQ facies, and BOQ facies so that the ore shoot potential is 1-14 ppm Au.