TZ260AL4: Smithsonite pseudomorphic growths after scalenohedral Calcite crystals. The specimen shows growth of a successive series of layers that indicate that the Calcite was partially replaced in a first phase and finally ended up being totally replaced by Smithsonite.
San Antonio Mine (San Antonio el Grande Mine), level 8, East Camp, Santa Eulalia District, Municipio Aquiles Serdán, Chihuahua  Mexico (04/2013)

Specimen size: 3.2 × 2.4 × 2.4 cm = 1.26” × 0.94” × 0.94”

Main crystal size: 2.4 × 1.2 cm = 0.94” × 0.47”