ANDRADITE VAR. TOPAZOLITE

ABOUT THE SPECIMEN

Gorgeous large cluster of topazolite, a variety of andradite garnet. An excellent coverage of crystals is visible on all sides and the color is especially rich for Cerro de la Concordia. Under fluorescent lighting the crystals are buttery yellow, more yellow-green under incandescent lighting. The majority of them are super well crystallized, and in amazing condition. Superb example of this andradite varietal!

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MORE INFO

Cerro de la Concordia is better known in collector circles as a source of amethyst, making the 2014 GIA-documented discovery of topazolite here genuinely unexpected - the first formally confirmed occurrence of the variety in Mexico. The deposit is a contact skarn formed at the boundary between Cretaceous limestone and granodiorite intrusions approximately 50 km southeast of Valle de Veracruz, where iron- and calcium-rich hydrothermal metasomatism at roughly 400–600°C produced andradite-dominant garnet alongside calcite and chalcedony. Iron in the crystal structure drives the yellow to yellow-brown color - topazolite representing the iron-rich, non-chromiferous end of the andradite spectrum, in contrast to the chrome-bearing demantoid that also occurs at the locality. Crystals are rhombic dodecahedra, typically 1–2.5 cm, with a high refractive index producing a distinctly resinous to subadamantine luster. Microprobe analysis confirmed high iron content with Mössbauer spectra consistent with other documented topazolites, and the crystals are inert under both UV wavelengths - distinguishing them from some superficially similar garnets. Production has been periodic rather than continuous, with a 2021 find refreshing supply after years of scarcity; the locality remains underappreciated internationally given that Mexico is not traditionally associated with fine andradite.