Rubbish

Unidentified Substance 5 is a type of refuse found in the Biosphere's Scrap Block and nearby unnamed rooms in Metroid: Other M. It can be destroyed using Bombs or Missiles, and although the texture of the piles appears to be that of shredded paper, when destroyed it melts in a fashion similar to metal. Compressed cubes of the substance can be found blocking several Morph Ball tunnels, released from dispensers in the ceiling.