Green’s Dictionary of Slang

gunge n.2

[abbr. gungeon n.]
(US drugs)

1. potent marijuana.

[US]Pepper & Pepper Straight Life 67: Every now and then I’d run into some pot. They had what they called Gunje, which was black.

2. heroin.

Prison Poetry 35: Heroin...called...horse...dope...gunge [HDAS].