Supposed to be loaded with trace minerals - comes from volcanic ash - from what I've read so far it is used as both an organic plant fertilize as well as a healthy addition - in very small amounts - for livestock, including poultry - resulting in increased egg production and less loss of color over time in the eggs of dark egg layers. Interested to know if anyone here has experience using with their flock and if so, any positive or negative results from using it? I copied this description of it from a company that mines, bags and markets it internationally - AZOMITE 'This naturally mined, volcanic mineral has over 66 minerals and trace elements that are important for plant nutrition and growth. It improves depleted soils. Apply with compost, humus, manures, or other fertilizers to provide additional levels of nitrogen, phosphorus, and potassium. Will not burn plants. AZOMITE®, the "A to Z of Minerals Including Trace Elements", is a naturally mined mineral product that requires no mixing. It is odorless, won't burn plants and won't restrict aeration or water penetration. Unlike some products, AZOMITE® is not a manufactured, chemically prepared fertilizer. It is 100% natural with no additives, synthetics or filters. Mineralogically, the material can be described as a rhyolitic tuff breccia, which is a hard rock formation formed from the dust of a volcano that exploded. Its uniqueness stems from the multitude of trace minerals found in the deposit. Chemically, AZOMITE® is a hydrated sodium calcium aluminosilicate (HSCAS) containing other minerals and trace elements which the National Research Council recognizes to be essential. HSCAS is listed in the U.S. Code of Federal Regulations (21 CFR 582.2729) as an anti-caking agent, and is generally recognized as safe (GRAS) by the FDA"