Recognition of ancient pyroclastic rocks made up of particles of explosive volcanic origin and deposited by
primary volcanic processes and/or rapid sedimentation of freshly erupted, texturally unmodified particles
vis-a-vis secondary volcaniclastic deposits derived by significant reworking during transport of primary
volcanic particles prior to deposition, but long after volcanism (epiclastic) remains a major challenge. A
volcanic conglomerate having both rhyolitic clasts and matrix within the ${\sim}$2.5 Ga Bijli Rhyolite in the
Dongargarh large igneous province in the Bastar craton, is earlier interpreted to be of epiclastic origin,
primarily because of the presence of large rounded rhyolite clasts imparting conglomeratic appearance to
the deposit, and thereby considered representing a significant time break (unconformity) between
explosive Bijli volcanism and the deposit. Based on new field and petrography studies, we identified the
${\sim}$125 m thick volcanic conglomerate as rapidly sedimented texturally unmodified rhyolitic brecciaconglomerate
linked to coeval incipiently welded pyroclastic flow that occurred during caldera collapse
related to mafic-recharge-mediated Bijli volcanism, without significant time break. We ascribed the
rounding of rhyolite clasts to surface tension of hot crystallising molten magma in plastic state and partly
to mechanical interactions of particles on steep slopes in such volcanic settings. This study may help
clarify origin of similar deposits in deformed metamorphosed provinces elsewhere.