Rockhounding In Colorado: Where To Find Geodes
The disease strikes when least expected. You’re out for a hike and something on the path catches your eye. You see a small fossil, a shiny stone or a glimmering crystal and, naturally, you pick it up. Soon, the ground becomes a treasure trove of things to be looked at, turned over, scrutinized and pocketed. Once this happens, there’s no turning back. Rock-hound fever has struck.
For inveterate hikers and trekkers who explore Colorado’s mountains and forests regularly, these surprises add another dimension to the experience: That pretty, little green stone may be jade or amazonite; what looks like glass that washed out of a hillside might be a quartz crystal; the round, rough-hewn rock could be a geode.
Colorado offers an abundance of minerals, gemstones, crystals and fossils to anyone willing to go out and look for them. For the casual collector or the obsessed amateur, there’s a little something for everyone, just about everywhere. It’s a matter of paying attention.
Once the newbie hound is hooked, it helps to understand the terms rock and mineral, and how the two are related.
First, there’s no such thing as “just a rock.” A rock is more than an aggregate of minerals. Rocks are the history books of ancient geologic times. They include limestone, granite, sandstone and shale, as well as gravel beds, clay and even — can you believe? — the permafrost of Siberia. In fact, any deposit that makes up the Earth’s outer crust. And rocks are the preservers of fossils that once lived when Colorado was a vast sea.
But what about those other treasures hidden in rocks — the minerals that are at the heart of a collector’s expedition? A mineral is a naturally occurring, inorganic solid, and has its own characteristic crystalline structure. Gems, then, are the flowers of the minerals that have ornamental value because of their beauty, durability and, occasionally, some degree of rarity.
Colorado ranks among the most strongly mineralized areas in the world, and it’s especially noted for alabaster, amethyst, lapis lazuli (blue sapphire), topaz and turquoise. Its most characteristic gem is amazonite, the bright green mineral that is often mistaken for jade. But, hey, you don’t know what’s going to turn up when you’re out in the woods.
The Colorado landscape has changed dramatically in the last 10 years, with public lands becoming private, claims being staked and roads leading to closed gates. But the fun is still there if you know where there is public access. And one of the best resources is membership in the Colorado Mineral Society (CMS).
CMS has access to areas not always available to the beginner going it alone, and can help guide newbies as to where to go and what to look for. After a few field trips with seasoned explorers, you will discover how to recognize crystal- and gem-bearing rocks, as well as learn about local geology and topography.
CMS 2017 Summer Field Trip Schedule:
The adventurous rock hound wanting to venture further in search of lovely stones and crystals should go to www.peaktopeak.com/colorado/index.php3, an excellent Web site where you can access locations and availability for any mineral.
Next, get the most recently published guide to rock hounding in Colorado that describes the sites and includes directions and maps. For examples of rocks and minerals that occur in our region, it’s a good idea to visit a rock shop. Then pack a pick and shovel and head out to those beautiful, productive areas that are open to collecting.
The beauty of rock hounding is its simplicity. Walking around with your nose to the ground reopens that childhood part of us that thinks finding a pretty stone is a wondrous event. As a CMS member said after finding a lode of geodes, “It gives me a funny feeling, knowing how long they’ve been here waiting for me to find them.”
Did You Know?
Colorado’s state mineral is rhodochrosite (well-known areas are near Alma).
The state gem is aquamarine, found on the lofty reaches of Mount Antero (Chaffee County).
The state rock is marble from Yule.
The state fossil is the Stegosaurus.
Apache Tears, properly known as black obsidian (Ruby Mountain in Chaffee County), were named for the Indian legend that they are the petrified tears of Apache women mourning the slaughter of their men in battle.
Garo Park in Park County, still plentiful in blue agate and jasper, was the site of the last Ute Indian battle.
Garden Park near Cañon City, rich in geodes, quartz and fossils, is world-famous for its Jurassic dinosaurs and the role the specimens played in the infamous bone wars of the late 1880s. The dinosaur sites now form the Garden Park Paleontological Resource Area overseen by the Bureau of Land Management.
If you’re prospecting on Devil’s Head Mountain (Douglas County) in August, you’ll join millions of ladybugs for their annual gathering on the summit.
If You Go
Colorado Mineral Society, P.O. Box 280755, Lakewood, Colorado 80228; www.coloradomineralsociety.org
A good guidebook: Rockhounding Colorado (2004), by William A. and Cora Kappele
From the Editors: We spent a heap of time making sure this story was accurate when it was published, but of course, things can change. Please confirm the details before setting out in our great Centennial State.