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.
Mix designed to experiment with confined clay.
Gray, fine to medium-grained “Berea grit”.
Cemented glacial gravel.
Dark, waxy, bitumin-rich.
Sale
Compact Plant Fiber Masses.
Black, soft; most widely mined.
