Contin-Tail Rock & Mineral Show, Colorado’s largest outdoor show. Thursday through Sunday, 9am – 5pm. Free admission, Free parking. Over 100 dealers, gems, minerals, jewelry, cabochons, beads, fossils, petrified wood slabs, rough, tools, and equipment. In Buena Vista, at the Rodeo Grounds, near Rodeo Dr. and Gregg Dr., 343 US 24 81211.