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Aerial View of Cripple Creek and Victor Mine

Aerial View of Cripple Creek and Victor Mine

My seventh day touring mining towns in Colorado was spent in the vicinity of Goldfield and Victor in the Cripple Creek Mining District. I traveled to the American Eagles Overlook above the Cripple Creek and Victor Gold Mine and hiked on the Vindicator Valley Trail above Goldfield.

Headframe and Shops at the American Eagles Mine

Headframe and Shops at the American Eagles Mine

Since I had arrived in camp rather late the night before, I took all of the morning to recharge my batteries, literally and figuratively. My long trip the day before which started in South Fork and traveled through Creede, Lake City, and Gunnison had used up all the spare batteries I had for all my cameras, and I was still exhausted myself. I showered in the headquarters building of the KOA and finished setting up camp, making up my tent and sleeping bag for tonight. Then I spent the rest of the morning charging up my various camera batteries and spares in the game room while reading an old Andre Norton book on my iPad.

American Eagles Headframe

American Eagles Headframe

Finally in the afternoon I headed out, driving south and taking the gravel road up to the overlook. It crosses the main road used by the ore trucks taking overburden to the dump locations. I stopped on the way to look at the open pit mine operations of the Cripple Creek and Victor Mining Company, which is a wholly-owned subsidiary of AngloGold Ashanti. They are digging a huge pit down through what was the old Cresson Mine (the same mine that discovered the huge vug back in 1914, basically a large geode the size of a room lined with 60,000 troy ounces of gold). I’ll speak more about the open-pit mine tomorrow, because I took an excellent tour of it. While observing the operation, I used a time-lapse app on my iPad to record the huge trucks driving their loads out of the pit.

Panorama of the Cripple Creek and Victor Open Pit Gold Mine

Panorama of the Cripple Creek and Victor Open Pit Gold Mine

The American Eagles Mine was the highest mine in the district at 10,570 feet with one of the deepest shafts at 1540 feet. The land around it is a small spot of green surrounded on all sides by the CC&V operations. From there, one can see all the way to the Collegiate Peaks in the west and to Pike’s Peak to the northeast. Winfield Scott Stratton, whose famous Independence Mine turned him from an itinerant carpenter into the richest man in the district, bought the American Eagles Mine in 1895 as part of his consolidation of mines in the area. Today, the old headframe still stands with its double hoist and cage. Several out buildings, such as the shifter’s house and blacksmith shop, still stand as well. I spent a very pleasant hour at the top, reading the signs and enjoying the cool breeze.

Dumping Overburden from the CC&V Open Pit Mine

Dumping Overburden from the CC&V Open Pit Mine

Vindicator Valley with Headframe and Mill

Vindicator Valley with Headframe and Mill

On the way back down, I stopped and hiked the Vindicator Valley trail. This area lies between the overlook and the town of Goldfield. It includes the Vindicator Mine and Mill, with a large steel headframe and the decaying remains of the mill. I walked along the path, which is about 2 miles total. In places it was a bit of an uphill hike, and I should have been tired by the altitude, but I have grown acclimated and I actually felt better and more vigorous that I do at my normal 4500 feet.

Sign for the Vindicator Mine and Mill

Sign for the Vindicator Mine and Mill

All through the valley are many remnants of mining structures, such as powder magazines, ore bins and transport systems, headframes, and mills. Some of the structures have been moved here to preserve them from the CC&V operations. The company seems to have a real interest in preserving the history of the area, and Colorado overall does a much better job of this than Utah, where the only value seems to be to close the mines, cover the dumps, and pretend mining never happened.

Steel Headframe for the Vindicator Mine

Steel Headframe for the Vindicator Mine

Other structures I passed included the LaBella steam powered electric plant that was at the bottom of the trail and powered the operations in the area, the Gold Knob Mine (seen as wooden cribbing toward Goldfield), and the Theresa Mine headframe. This mine was active from about 1895 through the 1950s. It was closed during World War II, as was all gold and silver mining in the country. By the time the mines reopened, so much work was needed to repair and upgrade them that most of the mines closed. It wasn’t until the 1970s that gold operations started up again, mostly leaching of old low-grade mine waste and some small open pit operations. But in the 1990s a large-scale open pit mining operation was engineered and begun which is now the CC&V mine. As the mine has grown, so have the piles of overburden rock, seen on the upper slopes of Vindicator Valley.

LaBella Electric Plant Site

LaBella Electric Plant Site

From photos I’ve seen of what the area around Victor looked like in the early 1900s, things have changed quite a bit. Many of these mines, such as the Theresa, were worked off and on from the 1890s through the 1950s, and many original wooden headframes were eventually replaced by steel headframes.

Theresa Mine Headframe

Theresa Mine Headframe

Some structures were torn down for scrap metal, others were destroyed by time. Some, such as the Lillie Mine and Mill, were bought out by other companies (such as the Vindicator Mine or the Gold Cycle Mining Group owned by David Moffat and A. E. Carlton, which bought up many of the defunct claims) and their buildings were torn down and foundations buried by waste rock. In the 1970s and 80s much of this waste rock (huge piles of it) were dug up and processed using the leach pile method to recover gold from the marginal ores. This changed the look of the valley and moderated it. The CC&V mine has done a lot to reclaim the slopes and replant native species, such as areas of pine trees growing throughout the valley. They have reinforced some of the structures and built the trail systems with interpretive signs.

Anna J. Mine looking up Vindicator Valley to the American Eagles Overlook.

Anna J. Mine looking up Vindicator Valley to the American Eagles Overlook.

Powder Magazine. The explosives had to be kept separately from the mines to prevent accidental destruction.

Powder Magazine. The explosives had to be kept separately from the mines to prevent accidental destruction.

After this walk I drove into Victor at sunset to try to buy a steak for supper, but the small grocery store only had hamburger. I did take some good photos of the town in nice lighting. Back at camp, sunset lingered as I cooked supper and took some additional photos of the grass and aspens around camp.

A Sign in Victor, Colorado explaining the bawdy side of town.

A Sign in Victor, Colorado explaining the bawdy side of town.

The Fortune Club in Victor, Colorado, known for its . . . er . . . entertainment.

The Fortune Club in Victor, Colorado, known for its . . . er . . . entertainment.

Third Street in Victor, Colorado.Third Street in Victor, Colorado.

The Back Side of Pike's Peak

The Back Side of Pike’s Peak

Aspens and Colorado Blue Spruce at my camp.

Aspens and Colorado Blue Spruce at my camp.

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The next videos that will be completed for the Elements Unearthed Project are two episodes on the sources, mining, refining, and uses of beryllium. I’ve written a few posts previously about this topic, and as I continue to organize and prepare materials to use in the videos (which will be edited over the next week), I have created several diagrams that describe the process used for surveying and developing open pit mines at the Brush Resources’ Spor Mt. mine site in western Utah. You might say, “Beryllium? Why should I care about some rare metal that I’ll never use in my lifetime?” But you’d be surprised. You are already using beryllium (for example, the electrical contacts inside the automatic windows of your car use a beryllium-copper alloy because it can handle frequent changes in heat and resists corrosion better than many other alloys). Beryllium is also an essential metal for medical, nuclear power, and aerospace applications. I’ll discuss more of beryllium’s uses and its refining and sources in a later post, but in this post let’s talk about how the bertrandite ore is mined.

Spor Mt. beryllium deposits

Location of Bertrandite in Western Utah

Mining Operations at Brush Resources

The bertrandite ore found in the Spor Mts. is very similar to clay (an aluminum silicate) and looks like common dirt except it has a slight pinkish color. It’s also associated with fluorspar or fluorite, which is often a deep blue to violet color. One is tempted to think the more colorful fluorite is the mineral we want, but it’s actually the crumbly pink coating found on the fluorite nodules. Elsewhere in the Spor Mts., the fluorite has been mined commercially.

The first attempt at mining the bertrandite ore was started by Anaconda on their claim. They tried hard rock mining, but the soft altered rhyolite of the ore body proved too dangerous to mine that way.  One day, while the miners were all having lunch, the mine caved in. Fortunately no one was hurt, but it was determined then that the only safe method was open pit mining.

Exploratory drilling

Exploratory core drilling

Potential mine sites are surveyed by drilling core samples every 100 feet to map out the general location of the ore bodies. The bertrandite deposits in the Spor Mts. are located in a mineralized zone of altered rhyolite tuff that overlies a bedrock of limestone. This soft and crumbly altered layer is overlaid by a tough, hard layer of unaltered rhyolite with about the same composition and hardness of granite. All of this is further overlaid by a layer of gravel, loose rock, and sand deposited by Lake Bonneville during the last ice age. Since the ore body is tilted, it occasionally reaches the surface (where it was originally discovered) and in other places dips so far below ground as to be unfeasible to mine. Several mine sites, such as the Blue Chalk and Roadside I sites have already been mined, but enough reserves have been mapped to last at least 50 more years at current production levels.

Planning an Open Pit Mine

Planning an Open Pit Mine

Once the location of the ore body has been generally mapped out, mining engineers plan out an open pit structure that will reach the ore with the least disturbance to the overlying layers while keeping the sides of the pit terraced to safely prevent rockslides and excessive erosion. Once the plan is approved, a contractor is hired to remove the overburden, usually in the winter and spring months. The loose alluvial gravel and soil is removed first and set aside for later reclamation. The hard rhyolite is blasted and removed, and the altered rhyolite layer is also removed to within about seven feet of the bertrandite ore.

Removing the Overburden

Removing the Overburden

A second phase of core drilling is carried out, with holes every 25 feet to more accurately map out the exact ore locations. For a typical ore body, between 40 and 60,000 cores are drilled and sampled every two feet. 3D structural maps are prepared to identify where various grades of ore are located. The ore is then removed carefully; a technician with a portable field berylometer walks before the bulldozer and stakes out the locations of the ore grades that are being removed; a self-loading scraper scoops up the ore and moves it to stockpiles where it is sorted by grade into the same pile. The ore is then transported by 18-wheeler to the processing plant near Delta, Utah, about 50 miles southeast. High-grade ore is mixed with low-grade ore so that all the bertrandite coming to the plant has about the same percentage of beryllium. The final ore has less than .65% beryllium, or about four pounds per ton.

Next Post: Refining Beryllium Ore

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