plural -s
: a mineral NaCa2Al5Si5O20.6H2O of the zeolite family consisting of a hydrous silicate of aluminum, calcium, and sodium, occurring generally in masses of a radiated structure or rarely in distinct orthorhombic crystals, and being snow-white when pure (hardness 5–5.5)

Word History


Thomas Thomson †1852 Scottish chemist + English -ite

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Dictionary Entries Near thomsonite

Cite this Entry

“Thomsonite.” Dictionary, Merriam-Webster, Accessed 20 May. 2024.

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