Having become enthused with agate collecting during our recent trips to Lake Superior, my wife and I have taken up the broader hobby of rock hunting. While I have long been interested in geology, plate tectonics, natural history, rock formations and landscapes, my knowledge regarding specific types of rock has been lacking and this seemed like a good opportunity to broaden my education.
Heading to our Colorado farm, we thus took along a copy of Gem Trails of Colorado, by James Mitchell, to guide our collecting efforts. Surprisingly, our first stop would be along the Republican River Valley on the High Plains of eastern Colorado, about 20 miles north of Burlington. There we scoured the Tertiary and Upper Cretaceous sediments for agates, jasper, opals and other gemstones, eroded from the Rockies and carried eastward by large, meandering rivers; petrified wood may also be found in that area. Today, we headed to Golden Gate Canyon, northwest of Golden, Colorado, where we searched outcrops of pegmatite for mica, black tourmaline and feldspar among many other colorful rocks of the Front Range foothills.
Like birdwatching and the study of wildflowers, rock hunting can be a frustrating experience for the beginner, attempting to compare samples and sightings with the limited illustrations in field guides. But, like the other disciplines of nature study, this endeavor will open our eyes to a whole new area of science and, in the process, make us better appreciate and understand the magnificent diversity of our planet. Besides, it will provide fodder for a wide assortment of blog topics!
