I found this in my backyard and would love to know what I'm looking at. It reminds me of a fossil. I live in Colorado, Denver-metro. The sample is about 2 inches top to bottom, weighs maybe .5 lb, dull luster, can scratch with penny. Filled with little crevices, holes that remind me of fossils. Spiderwebbed areas also. A few quartz-like minerals embedded, also areas of teeny crystals. The pinkish color in photo is true.