There's Quartz in Them Thar Hills

You can complete this cache without leaving your vehicle.

Go to the coordinates, you will find a quartz mine around 110 years old. This site is accessible by 4WD or high clearance vehicle most of the year except when there is deep snow. Don't be fooled by limited snow on Rampart Range Road. It can get much deeper off the main road. Be careful.

If you do much hiking in Colorado, you are bound to come across abandoned quartz mines; or what appear to be quartz mines.

The Colorado Gold Rush began west of Denver around 1858, nine years after gold was discovered in California. Colorado prospectors became known as "Fifty Niners." Had that moniker stuck better, Colorado's renowned football team might have a different name today. In 1891 Gold was discovered in the Pikes Peak region. Less well-known than the California gold rush, through the 1930s gold production in Colorado exceeded anything California ever produced. In the Pikes Peak region witness towns like Cripple Creek and Victor. "Gold Mesa," southeast of the corner of 21st Street and US Highway 24 in Colorado Springs is testament to the enormous amount of mining that resulted in a mountain-sized pile of gold tailings.

There are many ways to find gold in Earth's crust. One is finding quartz veins (reefs) and looking for seams and cracks where gold might be hiding. It turns out the same processes that formed quartz a billion years ago, also are responsible for forming gold.
In simple terms, quartz and gold were deposited within crevices and fractures in rock far below the earth by circulating hot water -- a "hydrothermal" process. While the vast majority of quartz veins do not contain gold, that didn't keep prospectors from digging giant holes in quartz veins to look.

Quartz formed in areas of "intrusion rock" ... (remnants of extrusive volcanic activitiy). Unlike every other 14,000 foot peak in Colorado, Pikes Peak is a solid "batholith." A billion years ago a bubble of magma rose under an area 50 miles in diameter. The magma never reached the surface, but created the Peak and the landscape 50 miles to the NNW of Pikes Peak. This batholith pushed Pikes Peak to over 14,000 feet exposing a mass of pink granite that underlies the entire region and is visible in many spots. During that "extrusion" a zillion cracks formed that exposed magma to water. "Intrusion" rock formed in some of those cracks.
Go to the coordinates. You will find one very large area of intrusion rock. There's a good chance this spot of quartz did not yield telltale gold signs, or the hole would be a lot bigger.

One theory of gold/quartz formation: A billion years ago, a mass of molten rock rose towards the surface from Earth's liquid metallic core. This caused the solid rock above to break and fracture. Once at the top, the molten rock (the batholith) cooled and also fractured permitting water to seep in from the surface to mix with virgin minerals. On contact with the hot rock, water became superheated steam. Boiling water under pressure can reach very high temperatures, hot enough break down minerals that would otherwise not dissolve in water.

Some of this water/steam, now full of minerals, circulated back to the surface. The water cooled and deposited its minerals. There were at least two processes in place: Cooler water cannot hold the minerals, so they precipitate out. Acidic water is better able to hold minerals, when it comes in contact with limestone (nearer the surface), it loses its acidity and the minerals are deposited.

Sometimes those minerals are quartz. Sometimes they are quartz AND gold with quartz forming first, the superheated water sometimes left gold behind in fractures in the quartz.

The short story if you are a miner: Look for quartz. You might find gold.

There are four things you need to do to log this Earthcache:

Define "Quartz Reef" and "Epithermal Vein" in your own words.
There are two main types of rocks (minerals) at this site. Name them.
Post a photo of yourself at the site.
Send me the answers to your questions.