Webster's 1913 Dictionary
PROTOMETALS
PROTOMETALS Pro `to *met "als, n. pl.
Defn: A finer form of metals, indicated by enhanced lines in their spark spectra (which are also observed in the spectra of some stars ), obtained at the highest available laboratory temperatures (Lockyer ); as protocalcium, protochromium, protocopper, protonickel,protosilicon, protostrontium, prototitanium, protovanadium. -- Pro `to *me *tal "ic (#), a.
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