The root √KUL was connected to gold and gold-coloured things throughout Tolkien’s life but gradually shifted in meaning. The earliest form of this root was ᴱ√KULU “gold” from the Qenya Lexicon of the 1910s (QL/49), but at this early stage it was connected to actual metallic gold as much as the colour, as opposed to ᴱQ. laure which was “magic” name of gold (LT1/100). In The Etymologies of the 1930s, ᴹ√KUL was first glossed “gold (metal)”, but was eventually revised to “golden-red” (replacing a rejected variant ᴹ√GUL), and metallic gold became ᴹQ. malta < ᴹ√SMAL “yellow” (Ety/SMAL) while ᴹQ. laure shifted in sense to “golden light” (Ety/GLAW(-R)).
Tolkien’s continued use of names like Q. Culúrien (S/38) and Q. culumalda “tree with hanging yellow blossoms (prob[ably] a laburnum)” (RC/626) indicate the continued validity of this root, though I suspect in later writings it primarily referred to a golden-red or orangish colour.
The root √KUL was connected to gold and gold-coloured things throughout Tolkien’s life but gradually shifted in meaning. The earliest form of this root was ᴱ√KULU “gold” from the Qenya Lexicon of the 1910s (QL/49), but at this early stage it was connected to actual metallic gold as much as the colour, as opposed to ᴱQ. laure which was “magic” name of gold (LT1/100). In The Etymologies of the 1930s, ᴹ√KUL was first glossed “gold (metal)”, but was eventually revised to “golden-red” (replacing a rejected variant ᴹ√GUL), and metallic gold became ᴹQ. malta < ᴹ√SMAL “yellow” (Ety/SMAL) while ᴹQ. laure shifted in sense to “golden light” (Ety/GLAW(-R)).
Tolkien’s continued use of names like Q. Culúrien (S/38) and Q. culumalda “tree with hanging yellow blossoms (prob[ably] a laburnum)” (RC/626) indicate the continued validity of this root, though I suspect in later writings it primarily referred to a golden-red or orangish colour.