As an adjective crumbly
is easy to break into small fragments; brittle or friable.
As a noun pararealgar is
(mineralogy) a crumbly arsenic sulfide material that forms gradually from realgar under exposure to light.
crumbly
English
Adjective
(er)
easy to break into small fragments; brittle or friable
pararealgar
Noun
(-)
(mineralogy) A crumbly arsenic sulfide material that forms gradually from realgar under exposure to light.