RX86R0: Small sharp crystals of Bismuth, very bright and partially coated by well-defined Quartz crystals. With the Bismuth there are elongated, brassy, not well-defined Bismuthinite crystals.

La Espuela de San Miguel Mine is a historic locality known for small occurrences of Bismuth and bismuth-bearing minerals, typically formed in low-temperature hydrothermal environments.
Geologically, the area belongs to the southern margin of the Iberian Massif, in the Los Pedroches domain, dominated by Hercynian granites and Paleozoic metamorphic rocks. Hydrothermal fluids circulating through fractures in the granites produced narrow veins containing sulfides and semimetal elements, including bismuth, which occurs as bright metallic aggregates or dispersed nodules within the vein structures.
La Espuela de San Miguel Mine, Villanueva de Córdoba, Comarca Los Pedroches, Córdoba, Andalusia  Spain (09/1960)

Specimen size: 6.3 × 4.7 × 5.2 cm = 2.48” × 1.85” × 2.05”

Main crystal size: 0.8 × 0.2 cm = 0.31”