Rockdust

Rock dust, also known as rock powders, rock minerals, rock flour, soil remineralization, and mineral fines, consists of finely crushed rock, processed by natural or mechanical means, containing minerals and trace elements widely used in organic farming practices.

The igneous rocks basalt and granite often contain the highest mineral content, whereas limestone, considered inferior in this consideration, is often deficient in the majority of essential macro-compounds, trace elements, and micronutrients.

Rock dust is not a fertilizer, for it lacks the qualifying levels of nitrogen, potassium, and phosphorus.

Rockdust is also the limestone-based product sprayed on walls inside underground coal mines to keep coal dust levels down. This is to prevent coal dust explosions and also to prevent the incidence of black lung disease.

Soil remineralization creates fertile soils by returning minerals to the soil which have been lost by erosion, leaching, and or over-farming. It functions the same way that the Earth does: during an Ice Age, glaciers crush rock onto the Earth's soil mantle, and winds blow the dust in the form of loess all over the globe. Volcanoes erupt, spewing forth minerals from deep within the Earth, and rushing rivers form mineral-rich alluvial deposits.

Rock dust is added to soil to improve fertility and has been tested since 1993 at the Sustainable Ecological Earth Regeneration Centre (SEER Centre) in Straloch, near Pitlochry, in Perth and Kinross, Scotland. Further testing has been undertaken by James Cook University, Townsville, Far North Queensland.

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