Carboniferous
rock; stone
【医】 calculi; calculus; lapis; litho-; petro-; stone
char; charcoal
【医】 anthraco-; carbo; charcoal; vegetable charcoal; xylanthrax
layer; region; stage; story; stratum; tier
【计】 layer
【医】 coat; lamella; lamellae; lamina; laminae; layer; strata; stratum