This Specimen has been sold.
.9" Fantastic Polished Fire Agate - Calvillo Mines, Mexico
This is an authentic, .9" wide polished fire agate specimen collected from the Calvillo Mines of Aguascalientes, Mexico. The agate displays top-quality iridescence when rotated under a light source.
Fire agate is a variety of chalcedony that often displays a metallic, shimmering iridescence known as adularescence or the Schiller Effect. It likely forms by means of fluid evaporation within a cavity that is already experiencing chalcedony deposition. In these cases, a thin iridescent film floating on the stagnant, silica-rich fluids forms as ferrous iron oxidizes when coming in contact with air in the cavity, producing ferric iron (Fe202). Once the cavity experiences a dry period, the film collapses onto the pre-existing chalcedony, depositing the iridescent layer that creates the fire effect. A following chalcedony band encloses the iridescent film inside the agate. This process can repeat over multiple periods of hydration and dehydration within the pocket.
SPECIES
Chalcedony var. Fire Agate
LOCATION
Calvillo Mines, Calvillo, Calvillo Municipality, Aguascalientes, Mexico
SIZE
.9 x .45"
CATEGORY
SUB CATEGORY
ITEM
#245829