THE piles of batako, mass-produced bricks, cover the rear part of Juminta’s house. At a glance, there is nothing special since they are simply batako, which are usually used for building purposes. However, upon closer examination, Juminta’s batako look slightly coarser than the ordinary batako. “They are made from gutter mud,” said Juminta, 25.

Juminta, a resident of Kampung Rawa Gaga Kumpeni in the Kamal subdistrict, West Jakarta, exhib