plural -s
: a white or reddish mineral approximately (K2,Na2,Ca)Al2Si4O12.4¹/₂ H2O consisting of a hydrous silicate of potassium, calcium, and aluminum, belonging to the zeolite family, and commonly occurring in complex often cruciform crystals (hardness 4–4.5, specific gravity 2.2)

Word History


William Phillips †1828 English mineralogist and geologist + English -ite

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Dictionary Entries Near phillipsite

Cite this Entry

“Phillipsite.” Dictionary, Merriam-Webster, Accessed 26 May. 2024.

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