Calcite

St. Andreasberg mining area, Goslar District, Harz, Lower Saxony/Niedersachsen  Germany

Specimen size: 5.5 × 5 × 3.4 cm = 2.17” × 1.97” × 1.34”
Main crystal size: 4.7 × 3 cm = 1.85” × 1.18”