Source:http://linkedlifedata.com/resource/umls/id/C0078755
MSH: Zeolites. A group of crystalline, hydrated alkali-aluminum silicates. They occur naturally in sedimentary and volcanic rocks, altered basalts, ores, and clay deposits. Some 40 known zeolite minerals and a great number of synthetic zeolites are available commercially. (From Merck Index, 11th ed)