petrifaction

nouns

the process of turning some plant material into stone by infiltration with water carrying mineral particles without changing the original shape
petrifaction, petrification
is derived from
petrify
a rock created by petrifaction; an organic object infiltrated with mineral matter and preserved in its original form
petrifaction
is derived from
petrify
is a type of (narrower)
a lump or mass of hard consolidated mineral matter
"he threw a rock at me"
rock, stone