An iron-ore mine owned by Cliffs Natural Resources in the Iron Range of Minnesota. NEW YORK ( TheStreet) -- Iron ore hasn't seen this much excitement since perhaps the dawn of the Iron Age (circa 1300 B.C.). Though it had been brewing for more than a year, a sea change swept across the iron-ore trade when BHP Billiton ( BHP) announced on Tuesday that it had struck agreements with a "substantial number" of steelmakers in Asia. Not only did the behemoth Australian mining concern hike its iron-ore price by 90% from 2009, it also, in combination with similar moves by Brazil's Vale ( VALE), killed the benchmark pricing system that had structured the miner-steelmaker relationship for the last four decades. The ramifications of the shift are just beginning to be felt, and they extend far beyond the Australian and Brazilian mining districts and the Chinese steel-mill zones that have come to define more than 70% of the world iron-ore business. From the assets of Cliffs Natural Resources ( CLF) in the Minnesotan Iron Range, to start-up mining entrepreneurs with dreams of exploiting huge ore bodies in remotest Canada, to the corporate corridors in steel towns like Pittsburgh and West Chester, Ohio, the changes to the benchmark iron ore pricing system, a seemingly international phenomenon, will eventually have an impact in good old North America. It all began about eight years ago, when China's breakneck growth fueled an unprecedented expansion of its homegrown steelmaking industry. Roads, bridges, buildings, factories: the need for steel grew so acute in China that demand for iron ore (steel's core ingredient) drove the world price of the raw material ever higher. By 2008, it had risen by some 375% over the previous several years. The global recession did nothing to dampen China's growth or its hunger for steel. All kinds of records were set in 2009: tons of steel produced, tons of iron ore imported, tons of iron ore extracted, even as the benchmark price a year ago fell by about 48% from the 2008 peak. With the price of the metal (chemical symbol Fe, atomic number 26, abundant in meteorites) shooting higher, the world's three biggest iron ore miners -- Vale, BHP and Rio Tinto ( RTP), in descending order of size -- began to politic for a change to the benchmark pricing system, in place since the 1960s.