Metal arsenates are chemical compounds formed by the combination of arsenic with metals. They typically consist of arsenic in the form of arsenate ions (AsO4^3-) and various metal cations, such as calcium, lead, or copper. These compounds can occur naturally in minerals or be synthesized for various applications, including agriculture and materials science. In agriculture, metal arsenates are sometimes used as pesticides or herbicides, although their use is regulated due to potential toxicity. Additionally, they can be found in some industrial processes and are studied for their properties in fields like geochemistry and environmental science.