granular flow (mimicking a liquid at larger scales) and was easily blown away by the bellow blasts, so was impossible to process using common methods of iron or steel production. Thus, innovative methods of smelting the ore were developed. The magnetite grains, however, often contain other metal impurities, such as chromium, arsenic, or titanium. Due to the nature of the sand the mining operations were rarely stationary, but frequently moved from place to place. Asia Historically, ironsand was predominantly used in Asian cultures; most notably in China and Japan. China Ironsand had moderate, localized uses in China during the late Industrial Revolution, but was a rather unimportant commodity throughout the long history of the Chinese iron-industry. Unlike the rest of Eurasia and Africa, there is very little archeological evidence to suggest that bloomery smelting was used in ancient China. The Chinese countryside was rich in deposits of both an iron ore containing a high content of phosphorus, and coal, a fuel that burns at a high temperature. Around 1200 BC the Chinese developed a method of smelting the rocky ore into pig iron, which was then remelted and poured into molds (cast) to form cast iron. Although the metal was very brittle, this method was able to produce iron in much greater volumes than bloomery smelting, and with vastly higher yields of metal per ore. By the 1st century BC the Chinese iron-industry was by far the largest and most advanced in the world. By the 1st century AD they had developed puddling for the production of mild steel, crucible steel for the manufacture of things like swords and weapons, and a chemical process of rapidly decarburizing liquid pig-iron to make wrought iron, using the oxidation properties of saltpeter (called the Heaton process, it was independently discovered by John Heaton in the 1860s). China remained the world's largest producer of iron until the 11th century, manufacturing large quantities of relatively affordable steel and iron. Donald B Wagner, an expert in ancient Chinese metallurgy, notes that attempts to trace the history of ironsand in China end with inconclusive results. One source may indicate its use as early as the Tang Dynasty (~ 700--900 AD) while others seem to contradict this interpretation. Due to wars, invasions, famines, distrust of the government, overpopulation, a rising opium epidemic, and clashes between various tongs of miners, very little information exists about the industry between the