Calcium iodide is an inorganic compound with the formula CaI2. It appears as a white or yellowish solid and is highly soluble in water. This compound is often used in various applications, including as a dietary supplement to provide iodine, which is essential for thyroid function. In addition to its nutritional uses, calcium iodide is utilized in laboratories and industries for its chemical properties. It can serve as a reagent in chemical reactions and is also used in photography and as a source of iodine in certain medical applications.