- Marcasite on Calcite
- Thumbnail, 2.9 x 2.8 x 2.1 cm
- San Antonio Mine, Santa Eulalia Mining District, Aquiles Serdan, Chihuahua, Mexico
- Ex. Irv Brown
This is a bright, unusual thumbnail specimen, featuring a rich mixture of textures and colors. A sharply-bladed cluster of metallic, bronze marcasite crystals are accented by a white calcite matrix. The marcasite has a beautiful patina, with a sepia-hued rainbow of color variation.