Some involve laboratory studies of rocks and other earth materials under high pressures and elevated temperatures.
Entisols differ from mere weathered earth materials (saprolite) by the partial formation of a surface horizon.
Recycling rare earth materials is particularly challenging as, once embedded in devices, they're difficult to take out.
"But to do that, American manufacturers need to have access to rare earth materials, which China supplies".
But it could do more to challenge other illegal policies, like China's ban on the export of rare earth materials used in high-tech industries.
They also can be created by disturbing the land, as in extraction, the moving of earth materials, or the disposal of waste products.
Scientists now recognize that macroscale behaviors, such as plate tectonics and mantle convection, arise from the microscale properties of Earth materials, including the smallest details of their atomic structures.
In her "Silueta" series (1973-1980) done in Iowa and Mexico, Mendieta left traces of her own body on earth materials: bowers of flowers, mud, tree branches and such, as seen in a group of poignant photographs.
