Fire Opal on Pale Matrix from the Carbonera Mine, Mexico

This fire opal specimen comes from the Carbonera Mine near La Trinidad in the municipality of Tequisquiapan, Querétaro, Mexico. Bright orange opal occurs within and on a pale volcanic matrix.

The fire opal forms a compact, irregularly bounded area that contrasts clearly with the whitish to cream-colored host rock. Depending on the lighting, the opal appears vivid orange to orange-brown. Its surface shows a waxy to slightly vitreous luster.

Measuring 2.5 × 2.5 × 1.5 cm, the piece belongs to the thumbnail specimen size category.

Fire Opal from the Carbonera Mine in Querétaro

The Carbonera Mine near La Trinidad is a well-known Mexican locality for fire opal. Opals from the region occur in volcanic rocks and fill cavities and fine fractures within the rhyolite.

Silica-bearing fluids entered these open spaces. The deposition of hydrous silica produced compact opal areas in various colors. Orange to reddish body colors are characteristic of fire opal.

The vivid opal color, pale rhyolite matrix, and precise locality information make this small piece a characteristic specimen from the Carbonera Mine.