hand samples of porphorytic textured rocks with red matrix

identification environment metamorphic sedimentary collecting geological geoscience unpolished coastline collector curiosity education formation inclusion resistant vesicular vesicules abrasion exemplar particle rounding sediment coastal fluvial geology igneous mineral science texture washing action pebble washed coast earth holes holey sized stone stony story gas raw pattern texture design lapidary raw rounded porphory abraded curious stones Isle Royal Michigan Royale olivine basalt mineralogy volcanology pockets solidification mineralization petrology rhyolite texture pink Department Interior Lake Superior amygdaloid amygdaloidal Keweenawan volcanic quartz geodes geodesic