Colorado Fossils and Rocks: 2023 Educational Outreach, Colorado Rocks Update

By Ginny Gent, Educational Outreach Committee Member

In early 2022 the Douglas County School District Library Media Center asked for our help with their mineral and rock kits. Their kits were missing samples and the all important key. We were able to replace the missing samples from our own stash of minerals and rocks and created a digital key that included links to www.geology.com mineral descriptions. The teacher feedback on the kits and new keys has been very positive.

During a visit to the Library Media Center, I was asked to look over their fossil kit that is loaned primarily to elementary and middle school classrooms. A little help was provided to make sure all the fossils were labeled correct and provided information on each fossil to the librarians for their records. While looking over the collection, it was observed they did not have any Colorado fossils. More importantly, they did not have a Mastodon fossil (a Mastodon was found during the building of a Doug Co elementary school).

Tyler Lyson, PhD and Curator of Vertebrate Paleontology at Denver Museum of Nature and Science was contacted and he agreed to help us with some fossils cast from their collection. Early this year we were able to give the Central Library six casts of Colorado fossils (Figure 1), a Tyrannosaurus tooth, Anzu Wyliei claw, two turtle skulls from Corral Bluffs, an Eoconodon skull (also from Corral Bluffs) and a Mastodon tooth. Both RMAG Educational Outreach Committee and the Douglas County School Central Library are eternal grateful for Dr. Lyson’s and his colleague Natalie Toth for all their help in making this donation possible.

Our call for Colorado Rocks has gotten off to a “rocking” start. Three RMAG members have donated a number of Colorado rocks from their personal collection. Fred Barnard of Golden donated a 25 cm long lava bomb specimen (Figure 2) from the Flat Tops along with a educational handout describing the bomb and what we can learn from lava bombs. Did you know ejected material’s temperature was between 1,100 and 2,100°F (600 to 1,100°C)? The bomb and the handout are a great addition to the Colorado rock collection.

Tim MacIntyre, PhD, donated several samples (Figure 3) from his graduate school work on the Chinle Formation at the Cashin Mine in Montrose County, Colorado. He also included a handout describing the soft rock metallic ore deposit found at the Cashin Mine. His samples include Wingate Sandstone with Cu mineralization, Chinle Formation showing bleaching along fractures and hydrocarbon staining, and a beautiful example of a burrowing layer in the Chinle Formation. These rocks are great educational examples of the mineral deposits found in the mineral belts of Colorado.

Terry Mather of Castle Rock gave us four rock samples for our Colorado Rock collection. Terry’s donation (Figure 4) included several samples of lava bombs from the Flat Tops that are a wonderful compliment to Fred’s lava bomb, a sample of the Dakota Formation with a great example of crossbedding from Horsetooth reservoir, a sample of Mahogany Oil Shale from the Green River Formation in western Colorado and several pieces of petrified wood from near Kiowa Colorado. This donation shows the wide variety of rock types and resources found within our boarders.

Thank you to all these fossil and rock donors for their work and donations. These donations will be used to education many students and youth on the geological processes and resources found in Colorado and may inspire a few to go on to careers in one of the many geoscience fields.