pseudomorph

pseudo- (“false”) +‎ -morph (“form”)

pseudomorph (plural pseudomorphs)

1. A deceptive, irregular, or false form; specifically:
   1. (geology, mineralogy) A mineral that formed by replacement of an existing mineral (or organic matter) such that the new mineral has the appearance and dimensions of the original.

      Petrified wood is a silicic pseudomorph of the original wood.

      • 1852, James D. Dana, A Manual of Mineralogy, page 54:

        The first kind of pseudomorphs, are pseudomorphs by alteration; the second, pseudomorphs by replacement; the third, pseudomorphs by infiltration; the fourth, pseudomorphs by incrustation.

• pseudomorphic

• pseudomorphism