Definition of "silver"

[…] maybe two or three twenties, a dozen tens, and twenty or thirty fins. The rest is all aces and silver.

1990, David F. Friedman, Don DeNevi, A Youth in Babylon: Confessions of a Trash-film King, page 136

And next morning they found him dead, with his neck broken, in the bottom of the stone pit, with his beautiful clothes a little bloody, and foul and stained with the duckweed from the pond. But his face was a face of such happiness that, had you seen it, you would have understood indeed how that he had died happy, never knowing that cool and streaming silver for the duckweed in the pond.

1909 April 10, H[erbert] G[eorge] Wells, “[The Time Machine and Other Stories]. The Beautiful Suit.”, in The Short Stories of H. G. Wells, London: Ernest Benn Limited […], published September 1927, pages 162–163

He looked round the poor room, at the distempered walls, and the bad engravings in meretricious frames, the crinkly paper and wax flowers on the chiffonier; and he thought of a room like Father Bryan's, with panelling, with cut glass, with tulips in silver pots, such a room as he had hoped to have for his own.

1918, W[illiam] B[abington] Maxwell, chapter X, in The Mirror and the Lamp, Indianapolis, Ind.: The Bobbs-Merrill Company

But Richmond […] appeared to lose himself in his own reflections. Some pickled crab, which he had not touched, had been removed with a damson pie; and his sister saw, peeping around the massive silver epergne that almost obscured him from her view, that he had eaten no more than a spoonful of that either.

1959, Georgette Heyer, chapter 1, in The Unknown Ajax

Mostly, these have been relationships of 10 or less years. However, one respondent has celebrated her silver wedding anniversary.

1994, “Mate matching” in Accent on Living, v 38, n 4 (Spring), p 52

Presently all the eastern sky began to silver and shine, and objects before invisible in the west—chiefly the tall towers on Mount Zion—emerged as from a shadowy depth, [...]

1880 November 12, Lew[is] Wallace, chapter IV, in Ben-Hur: A Tale of the Christ, New York, N.Y.: Harper & Brothers, […], book sixth, page 416

But when the moon rose and the breeze awakened, and the sedges stirred, and the cat's-paws raced across the moonlit ponds, and the far surf off Wonder Head intoned the hymn of the four winds, the trinity, earth and sky and water, became one thunderous symphony—a harmony of sound and colour silvered to a monochrome by the moon.

1907 August, Robert W[illiam] Chambers, “Silverside”, in The Younger Set, New York, N.Y.: D. Appleton & Company, page 281

For here retir'd the ſinking billows ſleep, / And ſmiling calmneſs ſilver'd o'er the deep.

1725, Homer, “Book X”, in [Alexander Pope], transl., The Odyssey of Homer. […], volume III, London: […] Bernard Lintot, page 17, lines 107–108

Remote from cities liv'd a Swain, / Unvex'd with all the cares of gain, / His head was ſilver'd o'er with age, / And long experience made him ſage; [...]

1727, [John] Gay, “Introduction to the Fables. The Shepherd and the Philosopher.”, in Fables, 2nd edition, volume I, London: […] J[acob] Tonson and J. Watts, published 1728