As three great Jewels they were in form. But not until the End, when Fëanor shall return who perished ere the… — J. R. R. Tolkien
As three great Jewels they were in form. But not until the End, when Fëanor shall return who perished ere the Sun was made, and sits now in the Halls of Awaiting and comes no more among his kin; not until the Sun passes and the Moon falls, shall it be known of what substance they were made. Like the crystal of diamonds it appeared, and yet was more strong than adamant, so that no violence could mar it or break it within the Kingdom of Arda.
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And an end was come for the Eldar of story and of song.
Sauron gathered into his hands all the remaining Rings of Power; and he dealt them out to the other peoples of Middle-earth, hoping thus to bring under his sway all those that desired secret power beyond the measure of their kind. Seven Rings he gave to the Dwarves; but to Men he gave nine, for Men proved in this matter as in others the readiest to his will.
Though this people used still their own speech, their kings and lords knew and spoke also the Elven tongue, which they had learned in the days of their alliance, and thus they held converse still with the Eldar, whether of Eressëa or of the west-lands of Middle-earth.

