Golden Yellow Calcite and Zebra Calcite

A lovely and large golden yellow and zebra striped Calcite specimen from Mexico. The bands of Calcite and Aragonite form alternating layers of white, black, gray and golden yellow. The color changes are a result of layered deposition in which different impurities resulted in varied colorations over time.

Calcite can form in a variety of colors and shapes. This piece formed in a massive-style deposit. Rather than forming into individual single crystals, the Calcite formed in a large vein, allowing it to be removed as larger pieces or "masses". The smooth, high-shine finish on this piece, and on many massive calcite specimens from Mexico, comes from two factors: calcite's natural waxy-to-vitreous luster and a standard mineral preparation process called acid-washing. During preparation, the rough specimen is dipped briefly in dilute acid. This both cleans the rock, and dissolves tiny surface micro-fractures and crumbles, leaving behind a smoother surface without adding any foreign materials, oils, or synthetic coatings to the stone. 

This specimen displays well from multiple angles, and even fluoresces under UV light!