To find it in quantities. A man strikes it rich when the quantity is unusually large.

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1867.  As for Dave, he and I have struck ile.—E. E. Hale, ‘The Man who stole a Meeting-House,’ Atlantic Monthly, xix. 111/1 (Jan.).

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1878.  Willie has struck chloride! He can sell out for fifty thousand dollars.—J. H. Beadle, ‘Western Wilds,’ p. 368.

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1890.  It was surmised from the size and weight of his sack that he had struck it rich.—Haskins, ‘Argonauts of California,’ p. 130.

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1909.  Wilson took his lunch in his hand and strolled up the side of Baxter Mountain. He climbed up on a large “blow-out” and seated himself to finish his dinner. The appearance of the rock struck him as peculiar, and he chipped off a fragment. Then he called his companions that he had struck it rich, and staked off the North Homestake mine.—N.Y. Evening Post, Oct. 28.

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