On Tuesday, September 13, 2016 at 2:06:01 PM UTC-7, Martin Gregorie wrote:

DU?

Please, Herr Gregorie, I hardly know you.

But seriously, I was wondering that myself. The last time I heard of DU in the context of materials, it was the _depleted uranium_ used for 30mm cannon shells of the A10 Warthog and the mass balances in early Boeing jetliners.

--Bob K.