A word for “metal” in Appendix F of The Lord of the Rings as the name of tengwa #1 [1] and the tincotéma series of tengwar. ᴹQ. tinko “metal” first appeared in The Etymologies of the 1930s under the root ᴹ√TINKŌ of the same meaning (Ety/TINKŌ). It also appeared in notes on The Feanorian Alphabet from the 1930s and 40s (PE22/22, 50, 61), already the name of tengwa #1 and its corresponding series.
Conceptual Development: A possible precursor is ᴱQ. sink (sinq-) “mineral, gem, metal” from the Qenya Lexicon of the 1910s under the early root ᴱ√SINI “pale blue” (QL/83). Hints of this earlier word can be seen in ✶sinkitamo >> sintamo “[metal] smith” in notes from the late 1960s.
A word for “metal” in The Etymologies of the 1930s under the root ᴹ√TINKŌ of the same meaning (Ety/TINKŌ).
Conceptual Development: A possible precursor is G. sinc “metal” from the Gnomish Lexicon (GL/67), a cognate of ᴱQ. sink “mineral, gem, metal” under the early root ᴱ√SINI “pale blue” in the contemporaneous Qenya Lexicon (QL/83). For purposes of Neo-Sindarin, I prefer to use ᴺS. sinc for “✱mineral”.