These pages tell a little about mining in the Crystal Peak area and describe the signs we are looking for.
I added pages to enlarge the photographs. Some are grainy, but until I get a chance to replace them, hopefully, they will be of help.
The Crystal Peak Mining District is an area north of Lake George, Park County, and Florissant, Teller County, Colorado. It encompasses a prominent peak, Crystal Peak, which for over a century has produced the world's finest combinations of amazonite and smoky quartz. The area of Pikes Peak Granite producing the miarolitic pockets and pegmatites extends from just north of Lake George east and west about three miles. The area then extends to the north for about six miles. Other outlying areas exist throughout the granite, but this has been the most prolific. In recent years the productive area has been reduced, because all of Crystal Peak and much of the surrounding area is now private property. Currently there are about 175 valid, unpatented mining claims located on the national forest mostly north and west of the peak.
Glacier Peak operates its own mining claims, Cut Dog, Smoky Hawk, Blue Smoky, Elk Horn, Wolf Fang, and several Qui-Buc No. 1, 3, and 8 claims. Additionally, we work with other mine owners on their claims and purchase specimens found by field collectors on open and private land (with permission!). Currently, two other companies are seriously mining in the region, but this can vary from year to year. Overall, we believe we place more Crystal Peak specimens on the market than anyone.
See Crystal Peak specimen information page for descriptions of the mineral species.
Good specimens of largely microcline, amazonite, and smoky quartz come from collapsed pockets in the Pikes Peak Granite. Both miarolitic (gas) cavities and pegmatite cavities produce good crystals.
Pegmatites: True pegmatites occur throughout the region. Most appear as quartz veins running for several feet linearly with the rock. Some pegmatites will begin as a very thin vein and gradually increase in size to where pockets are encountered. Others appear as solid veins of massive milky quartz which occasionally produce large pockets, primarily at the very deepest section of the pegmatite. These pegmatites have a distinctive zoning which helps in locating them. The country granite typically has about 1/8 to 1/4 inch sized anhedral crystals of feldspar and quartz. These crystals greatly increase in size, to several inches, as the pegmatite is encountered. Sometimes a thin band of small-grained granite (aplite) is seen bordering these much larger crystals. Feldspar is more predominant towards the edges of the pegmatite, while quartz becomes more prevalent in the core of the pegmatite. Blue-green microcline feldspar (amazonite) is never found in the country granite and only begins to show up in the pegmatites. If pockets occur, they can occur anywhere around the quartz core and along the entire length of the pegmatite vein. If the quartz appears smoky in color, a greater chance exists in finding a cavity. However, some of the largest pockets we have found have been found under "caps" of very uninteresting milky quartz. In other cases, we have excavated hundreds of feet of pegmatite without finding cavities.
Miarolitic Cavities: Miarolitic cavities can be likened to a gas bubble trapped in the cooling granite magma. Wherever a gas bubble is encountered, the feldspar and quartz crystals have an opportunity to form without contacts, and hence, they form beautiful euhedral crystals. Generally, the miarolitic cavities we encounter are small, about the size of a grapefruit and up to a watermelon. Unlike pegmatites, very little zoning is encountered and no quartz veins lead into the gas pocket, making them a little more difficult to find. However, almost always where one is found, a swarm of several will be found. And whereas a pegmatite often contains no cavities with crystals, the miarolitic pockets always do, making it worth the chance of blind digging. In one of our excavations, we keep peeling about a foot wide layer of granite rock off the wall to a depth of about twelve feet. Each layer reveals about six newly exposed gas pockets.
|An example of a miarolitic pocket.||Miarolitic pocket illustration. Joseph L. Dorris|
|A large pegmatite with small pockets.||Example of pegmatite with large-size subhedral crystals of microcline and smoky quartz.|
When prospecting for new gas pockets we do find some indications which are helpful. Most miarolitic cavities near the surface have spilled several pieces with large subhedral interlocking crystals of feldspar and smoky quartz. Sometimes euhedral crystals are found as floaters. Here is where we dig, and when opened, these pockets contain perfectly crystallized microclines, amazonites and smokies.
We use a backhoe or bulldozer to enable us to move the quantities of rock we move to get down to where the pockets are. There is little chance of damage to good pockets because we know we are approaching a cavity when we encounter bright red hematite-stained rock or clay. This material is almost always found within a pocket. In fact, when the red is hit, we are off the machinery inspecting carefully for crystals since nearly always we've topped a pocket. If it is a pocket, the machine is shut down and we collect by hand to prevent damaging the crystals.
|Watching the backhoe on Qui-Buc No. 2||A large amazonite pocket exposed|
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