Rock flour

Rock flour particles may travel great distances either suspended in water or carried by the wind, in the latter case forming deposits called loess.

Rock flour, artificial or natural, is a source of plant micronutrients (minerals trace elements) widely used in organic farming practices as a soil conditioner.

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.

Volcanoes erupt, spewing forth minerals from deep within the Earth, and rushing rivers form mineral-rich alluvial deposits.

[4] Thomas J. Goreau who wrote the book Geotherapy believed that mafic/ultra-mafic rock flour had a powerful effect in restoring trace minerals to soils, which increases the health and vigour of the Microorganism, Plantae, Animalia pathway and also sequesters carbon.

An early experimenter was the German miller, Julius Hensel, author of Bread from Stones, who reported successful results with steinmehl (stonemeal) in the 1890s.

While this originally was an alternative concept, increasing mainstream research has been devoted to soil amendment and other benefits of rock flour application: for instance, a pilot project on the use of glacial rock, granite and basaltic fines by the U.S. Department of Agriculture exists at the Henry A. Wallace Beltsville Agricultural Research Center.

The Soil Remineralization Forum was established with sponsorship from the Scottish Environment Protection Agency and has commissioned a portfolio of research into the benefits of using mineral fines.

The elements high in available 2+ valence electrons, calcium, iron and magnesium in particular contribute to paramagnetism in soil which aid in cation exchange capacity.