Questor share tip: Rio Tinto should benefit from a better year for miners Iron ore prices hit $158.50 a ton in China last week after slumping to a low of $86.50 in September on concerns the country's economy could suffer a hard landing. The price has now rebounded ahead of an expected increase in production as the new Beijing government reignites infrastructure spending. Indeed, Chinese imports hit a record last year, rising 8.4pc to 743.55m tons, according to domestic customs data. With GDP expected to grow to more than 8pc this year, another year of record imports is in prospect. Rio's copper operations also continue to show an improvement. Total mined copper production for 2012 was up 6pc year-on-year, due to expected recovery in the quality of copper at its mines at Kennecott Utah Copper and Escondida in Chile. The group's massive Oyu Tolgoi copper mine in Mongolia is expected to start commercial production in the middle of the year, so output should increase substantially this year and next. Rio also produces thermal coal, uranium, titanium and diamonds. Production was more or less in line with expectations. Rio has said that it is reviewing its diamond business, as it aims to focus on its core commodities of iron ore, copper and coal. The assets include the 100pcowned Argyle mine in Australia, which produces pink diamonds, a 60pc stake in the Diavik mine in Canada and 78pc of the Murowa mine in Zimbabwe. Earlier this week, US group Harry Winston Diamond Corp sold its luxury retail unit to Swiss group Swatch. Harry Winston owns the other 40pc of the Diavik mine and its chief executive, Robert A Gannicott, said that it may be interested in buying Rio's stake because it now has cash to spend. We are aware that Rio Tinto wants to sell its interest in the Diavik mine ... that's an obvious one for us to look at as long as the price is right," Mr Gannicott, said. However, there has been some speculation that Rio could spin off its diamond assets, which include marketing and processing operations, into a separate company listed in London. All-in-all these production figures look good and Rio is ideally positioned for a year that is likely to be far better for miners than the previous one. The shares are trading on a 2013 multiple of 9.9 times and the prospective yield is 3pc. Questor maintains a buy rating on the shares.