Calcium oxide, commonly known as lime, is a white, crystalline solid. Its color is primarily due to its chemical composition, which includes calcium and oxygen atoms arranged in a specific crystal lattice structure. This structure scatters light uniformly across the visible spectrum, resulting in the perception of white. The color of calcium oxide is consistent and does not change with temperature or other environmental factors. According to the Handbook of Inorganic Compounds, the color of calcium oxide is described as "white, crystalline." This information is supported by various scientific literature and research studies on the physical properties of calcium oxide.