Glencore International PLC reported that its marketing operations “continued to trade robustly” in the first quarter of 2012 and that it was making encouraging progress in a range of mine production expansion projects. Among its metals operations, tin showed the biggest increase relative to the first quarter of 2011. Copper and gold production also rose, while zinc, gold and nickel production fell.

Tin-in-concentrate production from Glencore’s Sinchi Wayra subsidiary in Bolivia rose 59% year-on-year to 650 tonnes. Concentrate comes from the Colquiri zinc-tin mine, which produced 2,200 tonnes of tin-in-concentrate in 2011, up by 16% on 2010.

Commenting on world market conditions the commodities giant said that “Glencore has traded well across all segments of its business in 2012. Physical demand for commodities remains broadly healthy across the globe, although precise conditions vary by location. US demand has continued to strengthen in areas such as automobiles and aerospace, while European conditions remain generally weaker. Overall Chinese demand continues to be healthy. It remains our view that available global inventories are generally low, both on exchanges and within supply chains.”