Prehnite w/ Apophyllite (Conneticut, USA) | Green Crystal, Rare Mineral SpecimenPrehnite from Connecticut is a classic and highly recognizable mineral in East Coast geology, especially from trap rock quarries in areas like Southbury, Woodbury, and East Granby. It typically forms in basaltic cavities where low grade hydrothermal fluids deposit minerals, producing its signature pale to medium green, translucent botryoidal masses that collectors often describe as having a waxy or gel like glow. Size: 4. 7 x 4 x 2 Cm Weight: 60g (