Mine output in South Africa, the world's biggest producer of platinum, fell 13% in the first quarter of 2009 compared to the previous three months.The fall was driven by the global recession which spurred companies to curb supply.Production of platinum and related metals declined 6.9% and diamonds 3.9%, Statistics South Africa said in a report on its website Thursday. Total March output in the country fell 4.6% from a year earlier.A newswire service reported that mining companies including Anglo Platinum, Lonmin and De Beers shut some operations after metal and gem prices plummeted.It further stated that the value of South Africa's mineral sales fell by a fifth in the three months ended February 28, from the previous three-month period. In February, sales dropped 12% to R19.4bn from a year earlier.