Mellyrn don't sing, do they?

[HerenIstarion]

Well, since question of singing gold 'things' seems settled (my compliments, Guinevere ), let us turn to mellyrn and their origin.

There were two waves of 'expansion' of mallorns to Middle-Earth, and both came from Valinor:

Second Age, through Númenor and Galadriel to Lothlórien

First Age, through exiled Noldor.

This latter has indirect evidence for a support:

Silm77, Of Eldamar and the Princes of the Eldalië

For all living things that are or have been in the Kingdom of Arda, save only the fell and evil creatures of Melkor, lived then in the land of Aman; and there also were many other creatures that have not been seen upon Middle-earth, and perhaps never now shall be, since the fashion of the world was changed

and

UT, Christopher Tolkien's notes to 'Of the Coming of Tuor To Gondolin'

A description of Gondolin was to follow, of the stairs up to its high platform, and its great gate; of the mounds (this word is uncertain) of mallorns, birches, and evergreen trees; of the Place of the Fountain, the King's tower on a pillared arcade, the King's house, and the banner of Fingolfin

The theory hence:

Since 'living things' include trees, and since only mention of mellyrn in Beleriand is in Gondolin, it is to be assumed that Noldor brought them originally. So, 'First Wave' - Valinor - Noldor - Gondolin. M-E mellyrn become extint with the drowning of Beleriand, and the 'Second Wave' comes again from Valinor though Tol Eressea and than Númenor

It would have been interesting to speculate about seeds that may have been saved by Tuor and been brought in time to Númenor, whence they would have been re-introduced to Middle-Earth through Tar-Aldarion and Galadriel, but quote provided by Guinevere (Trees brought by Elves of Tol Erëssea to Eldalondë) above forbids speculations of the kind

[Mithalwen]

Valley of the singing gold is a little poetic but if you think that Lorian elves actually lived in the trees and all elves love to sing it isn't that fanciful.

The use of singing and music as a expression of (for want of a better term though I think it unsatisfactory) magical power has been exprlored elsewhere but I would just say that Arwen the actual and symbolic heir of Luthien, the most notable proponent of this skill, sings while the sapling of the White Tree makes its unnaturally speedy growth and the mallorn seed, gift of the lady who sang of leaves of gold makes similarly freaky progress when Sam plants it in the Party Field.

Mallorns my be a more generic memory of Laurelin than the more specific likeness that the White trees of Numenor and Gondor are of Telperion but I think it is clear that they are the heirs in fact if not intention. It is possible that Tolkien wrote it without noticing the significance, and the mallorn was no more than a gift to a gardener and lover of trees, but if so it is the most beautiful and fitting coincidence that the final destruction of Melkor's servant, Sauron, is marked by the flourishing of two trees of silver and gold.