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The United States Mint at San Francisco

Fast Facts

Frisco Fast Fact
This facility was created as a result of the California Gold Rush of 1849.

The Story of the San Francisco Mint

Yesterday

For more than a century, the United States Mint at San Francisco has played a part in making our nation's coinage.  Here's how it all started.

In its first year, this facility made more than four million dollars worth of coins with the new "S" mint mark.
Image shows an engraving of the first United States Mint building in San Francisco.
An engraving of the first San Francisco Mint building, opened in 1854.
(Public domain)

In 1849, people began rushing to California.  They had heard stories of hills and rivers seemingly filled with gold.  Soon the miners of the Gold Rush found so much gold that President James Polk asked Congress to allow a new Mint branch to open in California.  With such a facility, California gold would no longer have to be sent to Philadelphia for coining—a slow and dangerous trip.  Congress agreed in July of 1852.

By April of 1854, a new facility had been built and its coin presses began turning miners' gold into coins.  By the year's end, more than four million dollars worth of coins had been produced, all bearing a new mint mark:  "S" for San Francisco.

But the building soon proved to be too small for the amount of work that needed to be done.  In 1874, a grand new building was finished.  In style, it looked similar to an ancient Greek temple, with thick walls of stone and brick and round columns at the entry.  This second building is known today by the nickname "the Granite Lady."

The Granite Lady was the largest and most productive of the United States Mint's facilities until a bigger building opened in Philadelphia in 1901.

Then, in 1906, a terrible earthquake broke some of San Francisco's underground gas pipes, causing gas to leak and to fuel fires that destroyed most of the city, including its banks.

Image shows the second building surrounded by rubble.
The second San Francisco building surrounded by the rubble of the 1906 earthquake and fires.  (Library of Congress, Historic American Buildings Survey)

The Granite Lady herself stood through both the earthquake and the firestorm, but without gas power, coins couldn't be made there for a while.  In the meantime, the building did special service as a bank for the people of San Francisco until the regular banks could reopen.  Money for rebuilding the city was also collected in this facility.  After the gas lines were fixed, coins were made in the Granite Lady once again until 1937.

At that time, an even larger, more modern building was constructed, and the work of the Mint at San Francisco was moved to a new home once more.


Today

Image shows the San Francisco building in 2005.
The third building in 2005.
(United States Mint)

Rather than making circulating coins, the San Francisco Mint now makes beautifully polished proof coins and coin sets—some of the finest coins made anywhere.  These coins still proudly bear the "S" mint mark, just like the gold coins that were made there back in 1854.

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San Francisco Stories


The Great Mint Mystery

A newspaper report from 1928 gives us a peek at the way this facility operated at the time.

People were wondering about the sign that appeared in 1918 on the door of the San Francisco Mint.  When this "Closed to Visitors Indefinitely" sign was still in place 10 years later, people began to wonder what the big secret was.

Was something being made in there besides coins?  Why were flames seen through the windows?  Were the workers searched and watched every day?

Early in 1928, after getting special permission from the Secretary of the Treasury, the San Francisco Chronicle sent a reporter into the Mint to find out the answers.  The San Francisco Mint's Superintendent, M.J. Kelly, gave the tour.

A Shocking Discovery

Superintendent Kelly calmly explained the working conditions at the United States Mint facility.  He assured the reporter that the workers were not watched by armed guards nor searched at any time.  Each worker was presumed honest as if he or she were a bank clerk.  A few special guards watched for burglars, but some of the workers also were armed for emergencies.

All that was checked was the weight of materials.  At the end of every day, the weight of coins, scraps, and residue were compared with the weight of the raw material that came in that same day.  If there was a difference, everyone was kept in the building until the discrepancy was resolved, the one case in which employees could be detained.

Kelly gave a startling demonstration by pressing a button on a wall.  As bells suddenly clanged throughout the building, workers appeared in each doorway pointing revolvers!  The terrified reporter realized that the building's security against thieves was excellent!

More Surprises

Continuing the tour, the Chronicle reporter was surprised at the way coins and gold bars were handled—tossed about rather carelessly, in his opinion.  When he tried to pick some coins off the floor and put them in their bins, the foreman said, "That's all right, just let 'em lay.  We'll sweep 'em up later."  And they did:  every speck of dust was swept up every day, for most of the dust was precious metal.  Not a shred was allowed to leave the building as trash.

The melting rooms contained the fires that people saw from the street.  The room was filled with smoke, which could only get out through the windows because the furnaces had no chimneys.  Chimneys would have allowed too much of the precious metals to escape the building into the air.

The Golden Scoops

In writing an article for the San Francisco Chronicle in 1928, a reporter was given a tour of the San Francisco building where United States Mint coins were made.  In the department where gold and silver were separated, the reporter was amazed to see that the workmen were using solid gold scoops.  Each scoop was valued at one thousand dollars!  (This was in the days when you could buy a new car for less than $2,000.)

The reason the scoops were made of gold is that acids were used in separating the metals.  If the scoops were made of any other metal, the acids would have eaten them away until they couldn't be used any more.  Gold was simply the most practical material for the purpose.

The front-page story appeared in the newspaper on March 11, 1928.

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Thieves Among Us

Some people get strange ideas about stealing our nation's assets.  Here are some examples.

In Sheep's Clothing

Could it be that Chief Clerk Walter Dimmick had betrayed the trust placed in him?  It certainly seemed that way when the San Francisco Mint discovered that six bags of gold coins were missing from one of the vaults, together worth $30,000!

Only someone who could open the vault and had free access to the building could have removed that many heavy coins without being detected.

The Chief Clerk, Walter Dimmick, was able to get into the vault at the time the money was stolen.  He was also the last one to count the bags of coins every night before the vaults were closed.  Yet he denied knowing where the money might be.

Since he had already been caught learning to sign the Superintendent's name (forgery), taking money from the pay envelopes of other Mint employees (theft), and stealing other government funds in his care, a jury eventually found him guilty of stealing the $30,000 in gold double eagles and of two other charges.

At 46 years old, Walter Dimmick began to serve his time (almost seven years of hard labor) at the San Quentin prison in California.  The 1,500 gold coins were never found.

Tunneling to Treasure

The very secure San Francisco Mint building may have been the target of burrowing thieves at the turn of the 20th century.  Though the building was made to withstand any earthquake, someone may have discovered the building's weakness—its Achilles' heel.

In December of 1901, watchmen at the San Francisco Mint began hearing muffled explosions about 4 a.m. for several nights.  They felt light shaking in the basement—though there was no earthquake activity.  Something was clearly wrong.

While an investigator searched the neighborhood for a tunnel, the Superintendent had the $70 million of gold coins moved up to a vault on the second floor.  He also found Mint records that showed that basement vaults C and D had no concrete foundations.  Built to be workrooms, they could easily be broken into through tunnels from below.

Image shows the second building in the early 1900s, with horse-drawn carriages in front.
The second San Francisco building, early 1900s.  (National Archives)

But by January 11, 1902, Leach reported that the noises had stopped.  Maybe moving the coins, adding guards, and searching the neighborhood were enough to make the culprits change their minds.  Or maybe it was the traffic.

As reported in the book This is San Francisco:  "It is said that a man tried to tunnel under Mission Street to the Mint's basement vaults.  For months, he burrowed there like a mole.  Halfway to his goal, the heavy Mission Street traffic jarred loose the ceiling of his tunnel.  It caved in, and he crawled from his hole more dead than alive."

So, if there was a tunnel, it probably no longer exists.  By now, it would have caved in because of heavy traffic or earthquakes, like the one in 1906.

Oh, Rats!

For some people, working around money creates a strong temptation to be dishonest.  That was certainly the case for one maintenance man at the US Mint in San Francisco, if the legend is true.

It seems the building had a problem with rats.  The maintenance man had the job of getting rid of the pests.  As rats died, he would throw them out a window into an alley, then pick them up at the end of the day and bring them to a garbage dump.

This particular man thought he could steal himself some gold by stuffing coins into the rats before he threw them out the window.  When he later picked up the rats, he removed their stolen cargo before bringing them to the dump.

Of course, when gold goes missing, people notice.  The man was caught before he got away with much loot and was quickly brought to justice.

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The Lady Stands

The year 1906 is famous among citizens of San Francisco as the year of the Great Earthquake and Fires.  About 2/3 of the city was completely destroyed and many died.  The earthquakes broke gas lines, which fueled the fires that raged through the mostly wooden structures of the city, burning for days.  Banks were closed, its vaults too hot to open.

Close to the center of town stood the stately United States Mint at San Francisco's second building, now commonly known as the Granite Lady.  Thanks to the earthquake safety that was designed into the building and the hard work of the people stationed at the Mint, the Granite Lady stood when the city around her was in ruins.

Her strength also helped the city get back on its feet after the disaster was over.  Learn more about it by visiting the Granite Lady in the Time Machine, 1906 era!

"Image shows the San Francisco buildilng on the front and the Treasury seal on the back.
This medal shows the building at San Francisco and the Treasury seal.
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