tourmaline tongs

tourmaline tongs: noun plural but sometimes singular in construction
: a simple form of polariscope consisting of two transparent plates of tourmaline cut parallel to the optic axis and mounted on a tongs-shaped support so that the object to be examined can be held between them and used especially by jewelers for distinguishing glass from crystal

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Tourmaline — Tour ma*line, n. [F. tourmaline, cf. It. turmalina, tormalina, NL. turmalina, turmalinus; all fr. tournamal, a name given to this stone in Ceylon.] (Min.) A mineral occurring usually in three sided or six sided prisms terminated by rhombohedral… … The Collaborative International Dictionary of English
tourmaline — tourmalinic /toor meuh lin ik/, adj. /toor meuh lin, leen /, n. any of a group of silicate minerals of complex composition, containing boron, aluminum, etc., usually black but having various colored, transparent varieties used as gems. Also,… … Universalium
turmaline — Tourmaline Tour ma*line, n. [F. tourmaline, cf. It. turmalina, tormalina, NL. turmalina, turmalinus; all fr. tournamal, a name given to this stone in Ceylon.] (Min.) A mineral occurring usually in three sided or six sided prisms terminated by… … The Collaborative International Dictionary of English
Hair iron — historical image of hair irons (top) A hair iron or hair tong is a tool used to change the structure of the hair using heat. There are three general kinds: curling irons, used to make the hair curly, straightening irons, commonly called… … Wikipedia
Draw plate — Two drawplates for different wire gauge Drawing silver wire by hand pulling A … Wikipedia

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