1lapid.implementpumice stone, very light and porous volcanic rock used to erase ink from parchment:
(
MS: s.xiii2
)
pumex: ponce
i 380
(
MS: s.xiii/xiv
)
Scriptor habeat [...] pumicem
(gloss: (L) punce) mordacem et planulam ad purgandum et equandum superficiem pergameni
i 188.167 and ii 79.167