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Thursday, October 3, 2013

Cripple Creek NGRR Part Two: A look at Railroad/ mining relationships.

Sometimes two things just make sense together.  The human riding the horse, peanut butter and jelly, a car and the road, the list goes on.  But nothing seems to have such a perfect fit than Mining and the railroads.

Mines need heavy equipment, and also need a way to haul vast amounts of material as cheaply as possible.  The railway needs to have industry, a reason to exist, which mines provide.  Without the railroad, mines in many places would not exist, and without the mines, many towns, cities, and many railroads would not exist.  This combination and relationship is seen very well in Colorado.  The railroad and mining grew up together, and both fell together.  At first glance, one would think that this relationship is over, however this is not true.  Railroads located near northeast Wyoming are currently hauling vast tonnages of coal fro the powder river basin to power plants and shipping centers across the Midwest.  Appalachia still maintains some mining railroad operations, and not to mention that the Mesabi range in Minnesota still has iron ore to unload.  Only in states such as Colorado does this relationship seem to be a distant dream.

There is a lot of information out on the web about gold mining and the railroads, so I'm not planning to go into great detail like the previous post, but I do want to touch all the bases, and this relationship is one of them.

The problem with mining in far-reaching areas was that it would be difficult to ship material back to processing plants.  Miners faced this in the Cripple creek district.  Even today, the pavement and gravel road that cars travel on is not exactly what you'd call easy driving.  Now imagine that instead of one tour bus, there are 50 rail cars each as heavy as a bus, and you are in charge of the train that must head up the hill from Colorado Springs, navigate the valleys which surround Pike's Peak, then you have to go over a pass on the opposite side of Pike's Peak than from where you came, and finally make a steep decent into a valley rich with gold.  Even the thought makes me not want to be an engineer (ironic right?)  But if the train engineers had it difficult imagine being the one in charge of choosing the route?  Surveyors had their work cut out for them. Below is a map from Colorado Directory webpage. Though not to scale, the map does give a general view of the area. The route the road takes on the map is roughly where the tracks went.

Image from www.coloradodirectory.com.  I do not own this image and has only been used for educational purposes.
Even after the railroads reached the mining district, there were still three problems to be solved:

  1. Transfer the ore from mine to the train.
  2. ship the loads safely over rough terrain to the mills for processing
  3. Unload the ore from the train to the mill.
Problem one.

As talked about in the previous post, mines had several systems of mining gold ore and bringing it to the surface.  The most common method at the time would be to run a shaft elevator into the network of tunnels and haul the ore up by the bucket.  From there the gold would be sorted (at some mines) into various sizes to be shipped to various mills.  Once the gold was extrcted, it still needed to be loaded onto the rail cars.

Where possible, mines had the railroads build a spur to the mine where the gold would be dumped from large bins into waiting rail cars.  However some Mines were on terrain too steep or not stable enough for large trains, therefore the railroad would resort to either a system of chutes running down from the mine to the loading bins, or the mines would build their own, minimum gauge railway to haul ore down the hill to the bins.  Cripple Creek has examples of all three methods of loading:

Here is a system of loading bins that was directly below the mine, allowing for ore to be loaded into railcars.

We can see old trestle bents from a narrow gauge line (24" gauge or less) that ran from a mine to the tailings pile, where excess and non-gold rock was deposited.

 This chute came directly from one of the mines and ended about 10 feet above the road.  This chute either ran to a bin, or ran from a bin directly to the rail car.
Using my finger as a reference, here we see some really light mining rail that cars would have rode on.  The capacity of this rail may only have been a few tons per section (length of one piece of rail).  This is much less than rail used by larger trains that carried 100's of tons rather than a few.

Mines and miners (always being creative) built or ordered equipment specialized for mining.  the most famous of these is probably the mining tram.  Many mining trams existed, some were built in the shops, others were built in factories.  Cripple Creek has many examples of equipment on rails:

 This is one of many specialized cars for hauling ore, and/or materials through the mine shafts.  If someone knows what this car is, please tell me by commenting below as I have no clue.

 This is an end-dump hopper where the car would run to the end of the track, and then the hopper would dump off the front of the car (right side?) and either into a chute, waiting mainline rail car, or a storage bin.
 In the Cripple Creek District Mining Museum, the staff have on display a large, motorized, side dump car.  A person rode on one end of the car, and a motor would propel the car down the tracks.  This is unique because this car did not need a separate engine to move the 1-2 tons of ore within the hopper.
 A small, 18" gauge mining cart that was end-dumping is on display at a pull off half way between Cripple Creek and Victor, CO.
 Perhaps the most famous of all mining cars is the classic V-dump car.  There were many forms of this car.  This type was effective because a whole train could be assembled and pulled by a small engine.  10-20 tons of dirt could then be unloaded at once rather than 1-2 tons.  Also this car could dump off either side, meaning that piles of ore could be accumulated more evenly in a bin, or in the mainline rail car itself.
 Not quite as famous, ut certainly a hard worker was the side dump car.  Again, many forms (including the V-dump) were made, all had pretty much the same design.

 Looking closely at this V-dump car, you can see the mechanism which the car was rotated on.  acting like two gears, a special cradle accompanied by an arc-shaped assembly was used to rotate the car without the hopper falling off or offsetting the balance.

 Here we can see another motorized dump car.  Below shows the various control mechanisms.

Problem two

Although these mining trams are neat, they weren't meant to go more than a few hundred yards.  Mainline railroads needed to come to the mines, or as close as they could, for the gold ore to be shipped effectively.  Priority one was that the gold had to be easy to off-load and load.  Two types of cars could be used; the gondola, or the hopper.

The gondola is a rail car that has a floor and four sides, and is set low.  This was a good, all around car to haul materials.  It's downside is that a gondola (or most of the types produced) couldn't be unloaded easily.  The Hopper was a much taller gondola, but had the addition of emptying by gravity. through openings in the bottoms of the car.  The designs for both were pretty simple and straight forward.

I am continuing to look for photos that relate to this part of the post, and unfortunately haven't struck lucky yet, so I cannot load any photos that are available for my use.

The route the trains took to go in and out of the mining district is through the mountains on the west side of Pikes Peak.  Referring to the map above, the railroads took a route heading from divide to cripple creek roughly where the road is, and from cripple creek to victor via a route that will be discussed in part three of this series of posts.

Problem three

Once out of the wilderness and back to civilization, the gold ore had to be unloaded and processed in large mills.  Mills of this time period was processed using the chlorination method, where chlorine was introduced.

The extraction and purification of gold through chlorination is simple chemistry.  I don't need to dive too deeply into this process, but essentially when gold ore is introduced to chlorine, the pure gold particles tend to attach themselves to the chlorine.  Later the chlorine is removed, and thus the gold falls out of solution so the gold deposits form, giving miners very pure gold.  This process worked much better than previous mechanical methods of extraction which were listed in part one of this series.

What modelers want to model however, is not chemistry but the physical movements of railroad cars in a mill.  I must apologize because I have not found an adequate source of information yet, but I promise to do a follow up later on when I stumble upon reliable information related to railroad, gold mill operations.

What I can tell you is that gold mills were very large structures, usually, and required dozens of cars daily.  However just like the railroads that carried the gold, the ore mills are now gone.  One fascinating feature about the mills that I can talk about is called a stamp mill.  The stamp mill's job in the refining process was simple, crush the gold ore into smaller fragments.  Large mines had a stamp mill attached to them that would break the gold into more manageable sizes, and so a Google search about stamp mills is very helpful for a modeler who wants to model one.

So this wraps up the hardest portion of the series to write.  you may wonder why this is, and the difficulty lies in that I have no information, yet this is a topic worth mentioning, so I feel bad for not being able to come up with more examples, but unfortunately those examples haven't been found yet.  But keep a look out down the road for a follow up when I find a good source of information that is available for my use.  If someone has found a reliable source, I urge you to please comment below with a link or some sort of search phrase that can be used.

Part three will finally get to the best piece of historical information still in the area, the Cripple Creek Narrow Gauge railway!

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