Hi all.
I've been finding a few of these kinds of stones in rockpile, Central MN, and find them to be fascinating; though I really have little idea what they are. They have very fine granules, many with red, green, yellow, brown colors and ringed, metal-like inclusions. Some, in fact, are magnetic...also, very heavy for their size (about that of a softball). Here is a selection of the types I am finding. Any observations that would help me understand these specimens' nature and origins would be great! The last two are basketball sized and very glassy, heavy and beautiful.
I've been finding a few of these kinds of stones in rockpile, Central MN, and find them to be fascinating; though I really have little idea what they are. They have very fine granules, many with red, green, yellow, brown colors and ringed, metal-like inclusions. Some, in fact, are magnetic...also, very heavy for their size (about that of a softball). Here is a selection of the types I am finding. Any observations that would help me understand these specimens' nature and origins would be great! The last two are basketball sized and very glassy, heavy and beautiful.
