Video of a strata full of these Ironstone Concretions. These rare formations were formed at the bottom of an ancient sea, as iron was rolled across the bottom by tides and waves, building up rock on the outside and a spherical shape; then sinking into the muddy bottom. Now they are being forced out of that strata (over more millions of years). For scale, they range from 8 to 12 feet in diameter. Color washed out of video by rain clouds and youtube.