The Exploration of the Nickel Laterite Deposits in Irian Barat, Indonesia

Abstract

Nickel-bea ring la terites developed in-situ on nickel-bea ring peridotites were examined during the period 1969-1971 at a number of loca lities in the Cyclops and Waigeo areas in Irian Barat, I nd ones ia. The lateri tes occur in both forested and unforested areas and as plateau and hillside types of deposits. The di stribution of chemical elements within the profile is similar to other tropica l nickel laterite deposits, i.e. , concentration of Al zOa and Fe in the nea r surface layers with an accompanying depletion of Si02 and MgO and concentration of nickel in the low iron portion of the profile. Exploration was by drilling (hand augers, mechanica l a ugers a nd coring drills) and tes t pits. Through 1971 more than 50,000 meters of drilling a nd testpitting were com pleted. Samples were a nalyzed for Ni, Co a nd Fe at PTPNI's chemica l la bora tory on Waigeo Island. All drilling information, chemica l anal yses and mining class ifica tions are being analyzed by data processing techniques. In late 1971 a 12,000 ton bul k sa mple was coll ected on Gag Island and shipped to Fort Saskat-chewan, Canada for testing and eva lu ation studies .