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Webster 1913 Edition

Noun.

[Named after

Smithson

Tennant

, an English chemist.]

(Min.)

A blackish lead-gray mineral, closely related to tetrahedrite. It is essentially a sulphide of arsenic and copper.

Noun.

[from Tennant.] A subspecies of gray copper; a mineral of a lead color, or iron black, massive or crystallized, found in Cornwall, England.