This is a vug lined with calcite crystals and elongated, sharp, brilliantly lustrous, dark green atacamite crystals. In excellent condition given the fragility of the material, there are a few incomplete crystals as is typical with these. While it was producing, the Lily Mine produced some of the finest atacamite specimens collected in the modern era and this is a great one. (Sadly, the Lily Mine is now closed.) A beautiful atacamite!