Humate in the Upper Cretaceous Fruitland Formation in northwestern New Mexico
— Robert W. Newcomer, John P. Nybo, and Jakob R. Newcomer

Humate is a naturally occurring, high humic acid content material. It is associated with weathered coal and humate-rich mudstones and shales in the Upper Cretaceous Fruitland Formation in northwestern New Mexico. These humate-bearing deposits have been mined primarily to produce humic substances used as soil amendments. Mining of humate in New Mexico started in the 1970s, and nearly 60,000 metric tons were mined by six operators in 2016. Humic substances are water soluble and are beneficial to soils and plants. They are high molecular weight molecules (generally between 5,000 to 50,000 g/mol), with complex structures, large surface areas and cation-exchange capacities, and multiple functional groups. These properties facilitate molecular binding to salts, metals, and hydrophobic compounds in soils and water. Humic substances may play a key role in controlling the aqueous concentrations, mobility, bioavailability and toxicity of contaminants in the environment.