Natrolite, a silicate mineral, has several synonyms or alternate names. One commonly used synonym of natrolite is soda-calcic zeolite, a reference to its chemical composition with sodium and calcium. Other synonyms include rinneite, a rare variant found in northeastern Brazil, and tetranatrolite, a variation with four water molecules per unit cell instead of two. Snowball zeolite is another alternate name, referencing its snowy white appearance. Finally, natrolite is sometimes referred to as natrolith, particularly in German literature. Regardless of what it's called, natrolite is prized by mineral collectors for its unique crystal formation and mineralogical properties.