Silica Gel is used in protecting goods against excess moisture, which can promote the growth of mold, spoilage and corrosion. Silicon dioxide is the primary component of silica gel that is treated into a granular or beaded form. As a desiccant, silica gel has a strong affinity for water molecules. Silica gel is available in packets or loose bulk for various purposes. Silica gel adsorbs moisture, which in effect, locks in moisture and limits the damaging results of humidity. There are several kinds, colors and sizes of silica gel. The three most commonly available colors for silica gel are white, blue indicating and orange indicating. Indicating silica gels are processed with moisture indicators that change color to show when the product is saturated and needs to be regenerated.