wollastoniteepidotepyroxene

Wollastoniteepidotepyroxene is a term used in some petrological discussions to describe a hypothetical phase that would combine wollastonite (CaSiO3) with an epidote-bearing pyroxene in calc-silicate rocks. It is not an established mineral species in major databases such as Mindat or the IMA, and no formal description exists in the current literature.

Conceptually, the phase would represent a solid solution or intergrowth between wollastonite and a epidote-rich pyroxene component, with chemical elements Ca, Si, O, and minor Al, Fe, Mg. The precise formula and crystal structure are not defined, and reported occurrences are speculative.

Geological environments where such a phase might occur include contact metamorphic zones or skarns where calc-silicate-rock protoliths interact with hydrothermal fluids, producing wollastonite and epidote-bearing pyroxenes. Under varying temperatures and fluid activities, exsolution or peritectic reactions could, in theory, yield a combined phase or tightly intergrown crystals.

If validated, wollastoniteepidotepyroxene would be discussed within mineralogical spectroscopy and crystallography, requiring X-ray diffraction and electron probe microanalysis to establish its symmetry, composition, and lattice parameters. It would be important to distinguish it from coexisting wollastonite and epidote-bearing pyroxenes and to define its stability range and occurrence.

See also wollastonite, epidote, pyroxene, calc-silicate minerals.