Arsenopyrite

Carrock Mine, Carrock Fell, Caldbeck Fells, Allerdale, former Cumberland, Cumbria  United Kingdom

Specimen size: 4.2 × 3.9 × 4.5 cm = 1.65” × 1.54” × 1.77”
Main crystal size: 1.4 × 1.1 cm = 0.55” × 0.43”