Cobalt(II) sulfate is a chemical compound with the formula CoSO4. It consists of cobalt in the +2 oxidation state and a sulfate ion. This compound typically appears as a blue crystalline solid and is soluble in water. Cobalt(II) sulfate is often used in various applications, including as a drying agent in paints and varnishes, and in the production of cobalt-based catalysts. In addition to its industrial uses, cobalt(II) sulfate is also important in agriculture as a micronutrient for plants. It provides essential cobalt, which is necessary for the growth of certain bacteria that help in nitrogen fixation. This makes it valuable for improving soil health and crop yields.