What's the adjective for stonifying? Here's the word you're looking for.
Included below are past participle and present participle forms for the
verbs stone, stonewall and stonify which may be used as adjectives within certain contexts.
“The handmade wall covering in the living room is stonelike in texture with a slight metallic gleam.”
“The term coral is also applied to the skeletons of those animals, particularly to those of the stonelike corals.”
“Another variable character in sponges is consistency, which may range from the soft and viscous state of some encrusting species to the hard stonelike quality of the genus Petrosia.”