Nepheline syenites are a type of igneous rock primarily composed of the mineral nepheline, along with other minerals such as feldspar and pyroxene. They typically form from the cooling and solidification of magma that is low in silica. This unique composition gives nepheline syenites a lighter color and a different texture compared to more common rocks like granite. These rocks are often found in areas with volcanic activity and are associated with alkaline magmas. Nepheline syenites are used in various applications, including ceramics and glass production, due to their low melting points and ability to improve the properties of the final products.