CCHS Rock Collection on Display

Several pieces from the historic Cañon City High School rock collection are now on display in the Learning Resource Center at Pueblo Community College – Fremont Campus.

Many of the rocks were collected during the early part of the twentieth century from Fremont County, providing a showcase of our rich mineral and mining history.

A sampling of the highlights of the display:

• Beryl – This 8″ tall hexagonal crystal was mined from a quarry to the west of PCC in Fremont County, either from 8 Mile Park near the Royal Gorge or a bit farther west. This specimen is not gem quality, but is probably a low-grade aquamarine.
• One of the largest beryl crystals was 5’11” in diameter, 11′ long, and weighed 40 tons. This beauty came from the Devil’s Hole Quarry west of Cañon City several years ago, and is owned by the Tezak family. Beryllium is used to harden steel.
• This crystal formed as igneous rock in a pegmatite. The Royal Gorge plateau is famous for its massive pegmatites sometimes hundreds to a few thousands of feet long and some 1.4-1.7 billion years old. Pegmatites are formed when magma from deep inside the earth bursts upward and intrudes into seams and cracks. Large crystals are formed when magma cools slowly, and with pegmatites, concentrated pockets of superheated water rich in dissolved ions aids in large crystal formation.

Copper – This beautiful native copper plate is from upper Michigan, a well-known location for copper and silver mining from 1843-1969.  This is elemental, pure copper, not combined with any other minerals.

Graphic Granite – A granite (igneous rock) from the Royal Gorge 8 Mile Park area.  Called ‘graphite’ due to the resemblance to cuniform writing, it is formed by the separation of the quartz (thin silver veins) from the feldspar (pale pink background), a process called exsolution.

Molybdenum – Not particularly pretty but highly valuable in large quantities, these specimens come from the world-famous Climax Mine in Lake and Summit Counties.  Affectionately referred to as ‘Moly’, this mineral is soft and used for hardening steel.

Pyrite and Galena – The bling of the mineral world, the gold pyrite cubes sparkle in the sunshine.  Under the pyrite are cubes of galena, a dark mineral which is the primary ore mineral of lead.

Limonite Dendrite on Manganese – Dendrites look like ferns embedded in rocks, fooling many people who assume they are plant fossils.  Instead, they are a superficial deposits of manganese oxide that crystallizes in a branching pattern.  This one is nature’s art, a sunrise on rock.