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Old SF Mint's lost treasure

One of the great rarities in the U.S. coinage series is the 1870-S gold $3. Only one specimen is known to exist. What isn’t known about this coin (and a unique 1870-S half dime) is if it is the specimen that was to be placed in the cornerstone of the Old San Francisco Mint (the Granite Lady) at Fifth and Mission streets, or if it is a second specimen. What also isn’t known, even though there are some tantalizing clues in newspaper articles from the period, is the current location of the cornerstone and its special contents.


The May 26, 1870 issue of the San Francisco Bulletin gives an account of the laying of the cornerstone, “this a huge block of granite, in which a cavity had been drilled for the reception of the casket, a copper box 6 inches high, 8 inches wide and 16 inches long,” for the new mint building.

Laying of the cornerstone began with a procession, as “members of the Masonic fraternity assembled at the Temple, on Montgomery street, and marched thence in full regalia to the spot, accompanied by the Second and Twelfth U.S. Artillery Bands. At 1:30 P.M., the procession filed down Mission street and into the inclosure, marching to its place between files of the Knights Templars with drawn swords and commanded by H.T. Graves.”

They were among some 5,000 attendees, as “Long before the hour set for the proceedings to begin, people commenced pouring through the gate and ranging themselves on the elevated seats erected on the northeast corner of the Mint building where the stone was laid…. “When all was ready for the ceremonies…Gen. La Grange, Superintendent of the Branch Mint…announced the invitation to the Grand Lodge to lay the cornerstone, and presented the working implements to the Grand Master.”

Among the items in the casket are minutes from state and city meetings; the latest state register, city directory and San Francisco almanac; maps of San Francisco and California; photos of San Francisco’s principal buildings; a piece of the first iron bar rolled from ores produced on the Pacific coast; samples of red, white and blue silk used for flags of the United States and California; a piece of Continental paper money dated 1776 (“valued at $800”); and one of each denomination of the 1870-dated coins struck at San Francisco.

It’s a treasure waiting to be found.