kieselguhr

noun1

1. •
   Diatomaceous earth, a kind of soft rock containing the remains of diatoms; it absorbs nitroglycerine and is used to manufacture dynamite.

   • It was the only name anybody seemed to know him by, “Kieselguhr” being a kind of fine clay, used to soak up nitroglycerine and stabilize it into dynamite. — 2006