That refers to the rock layer before Castle Rock Conglomerate that formed from mineral-rich, volcanic debris left by eruptions around the modern-day Sawatch Range.

And the Guida Farm Conservation Area in Middletown has one of the best Jurassic conglomerate rock formations in the state.The ledges are a mix of interesting rock shapes formed millions of years ago.

Now minerals form by erosion and chemical weathering of older minerals and rocks. However, most minerals formed some 1.3-to-2.3 ... forming a never before in earth's history seen type of conglomerate.

This is caused not only by the conglomerate nature of their makeup but from water getting trapped in denser layers, allowing algae to grow and form the darker colorations. The rocks have long been ...