The Role of Near-Earth Asteroids in Long-Term Platinum Supply

High-grade platinum-group metal concentrations have been identified in an abundant class of near-Earth asteroids known as LL Chondrites. The potential existence of a highvalue asteroid-derived mineral product is examined from an economic perspective to assess the possible impacts on long-term precious metal supply. It is hypothesized that extraterrestrial sources of platinum group metals will become available in the global marketplace in a 20-year time frame, based on current trends of growth in technology and increasing levels of human activities in near-Earth space. Current and projected trends in platinum supply and demand are cited from the relevant literature to provide an economic context and provide an example for evaluating the economic potential of future asteroidderived precious and strategic metals. Introduction: Since the launch of Sputnik in 1957, mankind has traveled a road of increasing dependence on the space frontier, rapidly advancing technology and creating industries that have become a vital part of global economic activity. Commercial activities in Earth orbit include broadcasting, telecommunications, remote sensing, weather monitoring and global positioning. Future commercial activities are expected to include microgravity manufacturing, entertainment and tourism. The bold and highly successful Apollo lunar missions have given way to a steady and growing human presence in orbit, as the International Space Station becomes the second operational facility with a permanent crew. The recent sale of the Russian MIR space station to a U.S. entrepreneur signals the serious intent of private enterprise to build and operate commercial human space facilities. Future trends in the development of space include the possibility of commercial lunar facilities (McKay, 1992 and O’Donnell, 1996) and associated lunar and asteroidal resource extraction. Long-term space-derived mineral product sales are expected to satisfy demand for fuel and construction materials in the growing orbital market as well as specific markets here on Earth. The Near-Earth asteroids are being catalogued at an increasing pace, and represent a source of materials with high geological diversity. Two classes of asteroid contain high concentrations of platinum group metals (PGMs): Metallic Asteroids and LL Chondrites. Members of both groups have been identified in orbital trajectories close to Earth, having the potential for significant transportation cost leverage. Up to 1000 times the payload can be inserted into low-earth orbit from a spacecraft departing one of these asteroids as an equivalent launch vehicle leaving the surface of Earth. O’Leary (1977), Lewis (1996) and Sonter (1998) have suggested mining products contained on these asteroids which have a high-value per unit mass. Platinum, rhodium, iridium, palladium and gold are found in significant concentrations (total PGM content exceeds 50 grams per ton) in meteorite samples attributed to the LL Chondrites, and enjoying high grades in certain