Great for biology and sediment studies.
Specially selected subsoil, 1 lb.
Specially selected topsoil, 1 lb.
4 pounds of limestone chips supplied in a box.
Brownish gray, kerogen-rich; commercial oil source.
Light gray, earthy.
Gray to buff, with numerous ooliths and fossil fragments.
Mix designed to experiment with confined clay.
Gray, fine to medium-grained “Berea grit”.
Cemented glacial gravel.