paramorph

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A mineral crystal formed or affected by paramorphism.

from The Century Dictionary.

• noun In mineralogy, a pseudomorph formed by a change in molecular structure without a change of chemical composition: thus, rutile occurs as a paramorph after brookite, and aragonite after calcite. See pseudomorph and paramorphism.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Min.) A kind of pseudomorph, in which there has been a change of physical characters, by a change in crystal structure without alteration of chemical composition, as the change of aragonite to calcite; called also allomorph.
• noun (Biol.) A taxonomic variant observed within a species, for which a more specific term has not been assigned.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun mineralogy A kind of pseudomorph in which there has been a change of physical characteristics without alteration of chemical composition, as in the change of aragonite to calcite.