RPT-In commodity pricing, silence and secrecy not limited to oil
* Cash commodity markets are subject to little regulation
* Lack of transparency in iron ore trading draws China's ire
* Steel body Eurofer thinks index prices can be manipulated
* Potash is one of most secretive, opaque commodity markets
By Manolo Serapio Jr
SINGAPORE, June 6 (Reuters) - A major European probe into the manipulation of global oil prices has raised concerns that could equally resonate across opaque cash markets for a host of raw materials ranging from iron ore to fertilizer.
Benchmarks established by journalists assessing the value of commodities are not unique to oil, and are used in markets for many raw materials to price cash contracts worth billions of dollars a day globally.
Producers, consumers and middlemen in those markets seek prices favourable to their business, and have leeway to be selective about what they reveal to the reporters assessing trade and prices. Continued...