A pulverized carbonaceous shale, it is an all-purpose “grits-to-dust” for adding minerals to growing media and sweeting soils. Builds mineral structure and adds carbon. Manages phosphorus leaching. A sedimentary clay mineral complex of high nutritive content including Nitrogen, Phosphorus, Potassium, Silicon, Calcium, Magnesium, Iron, Sulphur and significant traces including Vanadium, Zinc, Cobalt, Chromium, Copper, Molybdenum and Boron. Includes nearly 5% total carbon, 1% organic carbon and .1% total nitrogen. This material has alkaline earth elements which will tend to buffer acidic soils as the material weathers, can be a 50% substitute for lime. Manages Phosphorus run-off by capturing excessive solution reactive phosphorus.

One bag contains ONE pound of St George Black Rock Dust.