Depleted uranium is used as counterweights in the control system of many
aircraft. It is usually re-cycled when aircraft are junked. I also saw a
pair of DU penatraters from some tank rounds at an Army Surplus store, but
they wanted a young fortune for them. Far more than the metal content was
worth.

What in the world do you want to do with it any way? Its difficult to
machine, very hard, also its pyrophoric. Meaning the hot metal shavings have
a tendence to burn when exposed to the O2 in the air. Breathing the fumes
from this can be deadly, as others have mentioned DU gives off alpha
radiation, which is relatively safe, until it gets inside your lungs.