The Silver King Lode

Cherokee Park at upper right

Click any image to enlarge

By Richard I. Gibson

I’ve known that my 1898 house is set into mine waste since nearly the day I moved in, when I saw mica and pyrite on the basement floor. It was sloughing off the exposed wall beneath the stairs, where angular pyrite-bearing granite chunks and loose fine material were clearly visible. It wasn’t long before I learned that Uptown Butte’s parks mark old mine sites, but it was a good while before I discovered Sanborn maps and found that the park just north of my house, Cherokee Park (locals call it Cheese Park, but that’s another story), is the site of the Silver King Mine.

The black layer is probably decomposed wood

Last week, a hole opened up in the street maybe 40 feet from the northwest corner of my garage. It was only about a foot across, but the open drop into it was close to six feet deep. After numerous people came to look into it and paint variously colored marks on the pavement, on Tuesday a Butte-Silver Bow Public Works Department crew arrived to excavate the hole.

Soon the one-foot hole was 15 feet long and nearly as deep. Environmental Manager Tom Malloy pointed out the layers of fill – possibly some asphalt in the shallower zones, but mostly obvious mine waste like that in my basement, plus mixed coarse soil and rocks. We speculated that one black zone in the excavation wall, maybe three feet down, was coal or slag or charcoal. Eventually the excavator revealed a small hole at the bottom, presumably the sump taking water through the material, ultimately allowing for the collapse that made the original hole in the pavement up top.

Probably bedrock at left and
below debris (with brick) at right

Tom organized a water test; 1,000 gallons of water just went down, down, down. As he played water off the sides, I’m convinced he revealed at least three sides of an older hole made of solid (relatively solid) granite. Tom and I both think they were down to some original man-made cutting associated with the mine.

Close to my house!

The Silver King Claim extends from about the north side of Quartz Street to Copper in the west, and to the alley between Quartz and Copper in the east (it narrows eastward). On the west its boundary is about half way between Crystal and Clark, and on the east its limit lies between Idaho and Montana. My house on Crystal, north of the jog in Quartz, sits on the intersection of the Silver King, Plymouth, and Morning Sun claims. That jog in Quartz Street and the angling front yards of homes in the 600 block reflect the northern boundary of the Plymouth claim.

My lot is the red square

There were two Silver King mines and hoist works. Based on the Sanborns—and given the gaps in the years, it’s challenging to be certain, so I’m inferring from other evidence, such as the mine waste in my 1898 basement—I think the western shafts (where Cherokee Park is today) were in operation from about 1895 until about 1908. They were “not in operation Jan. 1910” on the 1914 map. The eastern mine was located at 210 West Quartz, between two houses (one still standing, at 208), directly north across the alley from the Copper King Mansion. That operation began after 1900 and worked until about 1915 (apparently working in 1914, but idle in 1916). There are tantalizing pasted-on updates in the physical 1914 Sanborn map (at the Butte-Silver Bow Public Archives) that suggest another hoist beneath the vacant lot at 521-527 West Quartz (a shaft was definitely there) – you can almost see through the pasted-on layers to older structures. I think the 1914 Sanborn is an update of a 1907 map set, but I’m not certain.

Red dots: modern road alongside Cherokee Park.
Blue oval: the excavation. 1914 Sanborn map.

At Cherokee Park north of my house, the operation had a main shaft in the southwestern part of what is now the park in 1900, with two boilers for generating steam and a 25-foot iron chimney. There was a secondary gallows frame and shaft, due north of my house about the width of my house away, along the south edge of the park or even under the street there today. The secondary headframe was connected to the main mine operation by two tramways, one to the northwest (about where the present-day street sits) to the western dump, and another to the north to dumps near the northern edge of the park along Copper Street. I think the relatively steep berm west of Cherokee Park is basically the Silver King mine dump.

House alignment on W. Quartz reflects
edge of Plymouth Claim

The mine complex was going strong in 1905 when Walter Harvey Weed, author of the 1912 US Geological Survey Professional Paper on Butte, visited. He apparently saw the 250-foot level, where he examined the Silver King vein, “remarkable for its richness and for the amount of gold which it carries.” He reported ore as high as 333 ounces of silver per ton and $294 in gold, also remarkable in that the metals were highly disseminated in what looked like ordinary decomposed granite, rather than concentrated in the quartz vein. Weed also noted a subsidiary vein branching to the west, a “very zincky vein.” (Note that the Anselmo, not far west of here, produced a lot of zinc.) Weed reported that “the yield of the Silver King vein has been rather phenomenal; and there was probably something like $150,000 in ore in sight at the time of visit (1905).”

Coppery shows in a rock from the dig

The vein dips to the south according to Weed, which may explain why the eastern Silver King mine shaft, at 210 West Quartz, was located off the claim itself. The hoist building there was in the lot near Quartz Street, but the gallows frame was nearer the alley between it and the Mansion. The dumps surrounded the headframe there.

Assuming that the Sanborn map is correct, the Cherokee Park Silver King mine operation ended at least 102 years ago, before 1910. The material in the excavation hole included a few bricks along with big loose rocks, all about 10 feet down; the suggestion is strong that there was a lot of filling going on even that long ago. I have not figured out when the curving extension of Crystal Street, along the southwestern edge of Cherokee Park, was installed. It does not show on the 1951 Sanborn map, while the house on the end of Crystal (in the middle of the street; address 535, and gone today) is still there together with the secondary headframe north of my house (301), so this area might have still been mine dumps as late as the 1950s.

LOTS of cement!

After pouring water into the hole, showing that it simply flowed on underground somewhere, the county crew plugged that deep hole with about 10 cubic yards of concrete, then filled in the rest of the excavation. Short of new pavement on the surface, it was good as new within hours, but what it hides below led me to this enjoyable investigation. If these electrons survive, maybe the next time someone has to excavate there (5? 25? 50? years from now?) they’ll have some sense of what to expect.

Funding for the B-SB Shaft Failure and Subsidence Mitigation Program is courtesy of the Montana Department of Natural Resources and Conservation (DNRC), Conservation and Resource Development Division, Resource Development Bureau, RIT Grant. Anywhere on the Butte Hill, if you see a suspicious hole in the ground, or even a curious depression, or an intriguing ground slump, the very first thing you should do, is to take three steps backward. Then call for assistance. BSB Planning Dept., Tom Malloy, 497-6257 or 490-4286.