PLATINUM futures prices fell sharply on Tuesday on the New York Mercantile Exchange amid a perception that South African production is rising and will offset a four-month delay in shipments of the metal from Russia. Platinum tumbled as the dollar strengthened against the rand. Since platinum is sold for dollars, there is an incentive to a producer with a weaker local currency to step up sales when the dollar is rising. This caused traders to anticipate an increase in South African production, driving down prices. South Africa produces about 70% of the world’s platinum and has boosted production recently amid good demand from jewelers and automobile companies.