What is humic acid?
Humic acid is derived from leonardite shale and is among the most concentrated organic material available. Elemental analysis of humic acid has shown it to consist largely of carbon and oxygen (about 50% and 40% respectively). It also contains hydrogen (about 5%), nitrogen (about 3%), phosphorous and sulfur (both less than 1%). Humic acid is a complex of closely related macromolecules. These molecules range in size from less than 1000 to more than 100,000 daltons, with the lower mass representing the younger material.