The Granite Lady.

You might have passed it on your way to the shopping center, or Blue Bottle Coffee—probably even unconsciously walking a bit faster, given the constant presence of some of the San Francisco’s loudest homeless on the building’s impressive staircase.

But this building, at the corner of the 5th and the Mission, is worth slowing down for. It is called the Old Mint today, although at its completion in 1874 it was actually the new mint, superseding the original one on Commercial Street, opened two decades prior, later bursting in its seams.

The building served as a mint from 1874 until 1937, when the third, current, New Mint—sitting on the hill at 155 Hermann Street—took over. But that’s only a tiny part of the fascinating story of the Old Mint, a building that could serve as a wonderful use case in Stewart Brand’s seminal book How buildings learn. During its lifetime it was important, then crucial, then abandoned; it was saved, then gutted; it changed its purpose many times over, and will soon be embarking on a completely new adventure. I took a tour—rarely offered, but opened to anyone curious—to learn more. Here are some of the things I found out.

The tour costs $10, unless you’re a member of the SF Museum and Historical Society (an organization that puts the tour all together and currently owns the building).

Waiting for people to arrive and the tour to start, I noticed the great meta-reflections of neighbouring buildings in the windows on the second floor.

But, truthfully, from the outside, The Old Mint won’t confess to too much. Most windows on the ground level look like this one.

It is when you go inside when things start getting interesting. We began our tour underground.

Every mint needs to be a fortress. The walls at the basement level are five feet thick, and so is the concrete floor below—this is all to prevent thieves burrowing or blasting their way in from underneath.

The use of granite on this level is where the building got its nickname “The Granite Lady” from (misleading as it is; overall there’s more sandstone than granite used in its construction).

In other buildings of that time, there were seven layers in between brick reversals—here, only three, which added to the stability of the whole construction. There are steel rebars hidden inside walls, too, for the same reason.

Some vaults on that level—much newer than the mint itself—are actually clad in metal for additional protection. In this particular room, silver dollars lingered for decades somewhere around mid-century. (Apparently no one likes silver dollars too much.)

On the day I visited, in August 2012, the ground level was used by a film crew to shoot a movie; we had to hurry while they were on a break. This vault was repurposed as a prop room.

You can still see impressions from the silver dollars pressing against the walls.

Another vault is temporarily used for the art department. The movie title’s is, if I heard it right, Sphere machine. That does not bode very well, I am afraid.

This is that particular vault; you can notice that the room wasn’t originally meant to be that and the windows needed to be bricked over.

Going up, the tour guide points out that there’s very little in the building that’s flammable. Even the white banisters are made from metal and painted; the handrail is just about the only thing constructed out of wood.

The corridors above are much more presentable than the underground level. At the time of the building’s opening, this was the only presence of the federal government on the west coast, so it needed to be impressive.

This was the first room you’d visit at the Mint during its early years of operation. You would deposit your gold here, with your eventual goal being getting the equivalent amount of legal tender coins.

Here’s another room, seemingly as distinguished as the previous one, but the tour guide assures us it’s an illusion.

A closer look at the floor reveals all sorts of cuts; back in the day you would find this room filled with machinery, noisy and vibrating—the grooves kept the equipment in place.

A quick look outside and one can notice San Francisco Chronicle as a neighbour. It’s a bit scary to look at both of these industries—finances and publishing—being turned upside down by technology. How long will the coins survive? How about printed newspapers? A decade or two from now, we shall know the outcome.

This courtyard was a place of a fiery battle with the post-earthquake fire of 1906. The building’s solid construction meant it didn’t suffer any structural damage from the tremors alone, but the fire surrounding it posed a much more difficult challenge.

The fire burned so hot, it melted the glass windows, exploded some of the sandstone and granite blocks, and burned shirts off people’s backs. Fortunately, the new water hose system was constructed just a week before, although the pump gave up during the earthquake and needed quick repairs. Imagine doing that as flaming cinders rain onto this courtyard for hours!

The devotion and ingenuity of people of the Mint—including its superintendent, Frank A. Leach, who took a ferry from Oakland to San Francisco at the moment everyone else was doing the exact opposite—ensured that the building stood. It was the only one left on the block, and the rare one with water, money (the other banks’s vaults were so hot, they were afraid of opening them for the fear of notes spontaneously combusting) and electricity in the weeks to come. It became a ground zero of relief efforts after the earthquake left the city in shambles. (You could even get a shave at the building’s entrance.)

You can read more about it all in an enthralling 2006 article from the Smithsonian, Grace under fire (PDF).

Saving the Mint also had financial repercussions. In this very place, up to one third of the nation’s gold reserves was held, until the day the United States Bullion Depository was opened at Fort Knox in 1937. Losing this much gold—some $300 million in 1906—would likely send the U.S. economy into tailspin.

Instead, only the smokestacks were casualties of the fire. By 1906 already unused, they were originally taller, with decorative endings which fell apart during the earthquake. You can see their youth in this abbreviated history of the Old Mint.

The real damage to the building came from an unexpected source. After the new mint took over, the old building was turned into a ramshackle Gold Rush museum (open to visitors until 1989), but also an office building. The new tenants “upgraded” the premises to the 1970s standards, which among other things meant—as you can see here—adding air conditioning to cool the power-hungry computers of the day.

This is the room, at the back of the building, that used to look like the other ones you saw before—but was, however, less lucky, being chosen for an “upgrade.”

In preparation for punch card mainframes installed here, it was almost completely gutted. Today, the computers long gone, it’s in a pretty sorry state.

Even the columns were cut away. Their stubs are painted orange so that the visitors don’t trip on them.

Fortunately, other rooms—like this beautiful corner one—can still hark back to the golden (har, har) days of the Old Mint. Some of the stamping machines for coins were located here. One of the first tasks of the new mint was to produce a twenty-cent piece, among the rarest coins in the U.S. history.

The legend has it that some sort of a time capsule, including coins minted at the first San Francisco mint, is buried somewhere underneath this room. However, the plaque that designated the specific location melted during the fire of 1906.

Those metal blinds are silent witnesses, and remember the frightening moments of the fire very well—they were literally red-hot that day.

(Those tacky curtains, much newer, are not silent witnesses to anything, except perhaps people rolling their eyes at their ugliness.)

This is the official entrance to the building, leading to the staircase outside, today unused. (Even the door knobs are gone.)

In the underground levels, parts of the Gold Rush exhibit still remain, reminding us of the building’s darker days.

How dark exactly? In the latter part of the last century, the building stood all but abandoned. But in 2003, its fortuned turned—the federal government sold it for a symbolic one dollar. The building’s purpose was to eventually be used as a permanent home of San Francisco Museum at the Mint. As the story goes, the $1 coin exchanged in the sale was one of the silver dollars minted here back in 1879.

The opening date for the museum moved from 2008 to 2012, and I suppose it will have to move again. The official website has more details about the plans for the museum and you can donate if the goal feels close to your heart. If you just want to watch pretty pictures, SF Museum and Historical Society has some nice rotating historical photos of the Mint on their homepage.

The surrounding buildings are already preparing for the change, and the entire place has been rechristened Mint Plaza.

Go visit the Old Mint building if you have a chance! It only costs an eagle, and it’ll be worth every half penny.

The New Mint (which just turned 75) doesn’t allow for visitors, but there’s a fantastic tour summary by Andrew Dudley from a website called Haighteration: part one and part two. Enjoy!