Any one of a family of hydrous alkali-aluminum silicate minerals, whose crystal lattice may enclose or sequester cations of sodium, potassium, magnesium, calcium, strontium, or barium, or a corresponding synthetic compound, used chiefly as molecular filters and ion-exchange agents.
[Swedish zeolit, from Greek zein, to boil (from its swelling and boiling under the blowpipe); see yes- in the Appendix of Indo-European roots.]
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