Division; available at http://periodic.lanl.gov/images/periodictable.pdf.Cover. Stillwater Mine in south-central Montana, looking southeast. The pond is the tailings impoundment. The buildings in the lower left include the shaft, the mill complex, and offices. Photograph by Michael L. Zientek, 2006.

Box plots and comparison circles for average platinum, palladium, rhodium, and gold grade of Merensky Reef mineral resource blocks located in the eastern, northwestern, and southwestern limbs of the Bushveld Complex, South Africa ............43 29. Box plots and comparison circles for average platinum, palladium, rhodium, and gold grade of UG2 Chromitite mineral resource blocks located in the eastern, northwestern, and southwestern limbs of the Bushveld Complex, South Africa ............44 30. Map of the Merensky Reef in western and eastern limbs of the Bushveld Complex, showing surface projection of mined portion of reef (mined out), portion for which exploration data is sufficient to calculate mineral inventory (resource block), and projection of where reef may extend to a depth of 3 km ..

Stratigraphic column of the Roan Group exposed in the Zambian part of the Central African Copperbelt showing the stratigraphic distribution of reduced-facies (argillite-hosted and mixed argillite-arenite) and sandstone (arenite-hosted

For more information on the USGS-the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1-888-ASK-USGS.For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprodTo order this and other USGS information products, visit

Acronyms and Abbreviations UsedA.D. Anno Domini-a designation used to label or number years used with the Gregorian calendar AGI American Geosciences Institute Ar-Ar argon-argon ArcGIS Esri's ArcGIS is a geographic information system (GIS) for working with maps and geographic information ASCII American Standard Code for Information Interchange BOMZ black ore main zone C.M.N. Calcaire à Minerais Noiŕ-Kambove Dolomite CACB Central African Copperbelt CAMEC Central African Mining and Exploration Company CAMI Cadastre Minier Corp. corporation CSK Comite Special du Katanga D. Strat. Dolomites stratifies-stratified, fine grained dolomites DEM digital elevation model DRC Democratic Republic of the Congo EMINERS Economic Mineral Resource Simulator Esri A software development and services company providing geographic information system software and geodatabase management applications g/t grams per metric ton Gécamines La Générale des Carrières et des Mines-a state-owned mining company in the Democratic Republic of the Congo GIS geographic information system ID identifier Inc. incorporated km kilometer km 2 square kilometers kml keyhole markup language-an extensible markup language notation for expressing geographic annotation and visualization within Internet-based, twodimensional maps and three-dimensional Earthbrowsers KOV Kamoto-Oliveira-Virgule area Ltd limited m meter Ma million of years before the present M.Sc. Master of Science xi Acronyms and Abbreviations Used n.b. nonbrecciated NGOs non-governmental organizations NI 43-101 National Instrument 43-101-guidelines developed by the Canadian Securities Administration for preparation of technical reports that summarize scientific and technical information concerning mineral exploration, development and production activities on a mineral property that is material to an issuer Plc public limited company R.A.T. Roches Argilo-Talqueuses Subgroup-red, massive-to irregularly bedded, terrigenous and dolomitic rocks R.S.C. Roches Siliceuses Cellulaires-massive and generally stromatolitic dolomites R.S.F. Roches Siliceuses Feuilletées-siliceous, laminated dolomites RCM Roan Consolidated Mines Ltd Re-Os rhenium-osmium S.D. Shales Dolomitiques-dolomitic shales S.D.B. Schistes Dolomitiques De Base-basal dolomitic shales S.D.S. Schistes Dolomitiques Supérieures-upper dolomitic shales Sprl société privée à responsabilité limitée-private limited liability company TCL Tanganyika Concessions Ltd UMHK Union Minière du Haut Katanga U-Pb uranium-lead USGS United States Geological Survey VTEM versatile time domain electromagnetic WGS World Geodetic System ZCCM Zambia Consolidated Copper Mines ZCCM-IH ZCCM Investments Holdings Plc.