Aesthetically emplaced on a matrix of massive calcite along with colorless, translucent quartz crystals, to 2 cm in length, are three fat, twinned, frosted and translucent calcite rhombs, to 7.5 cm in length. They are secondary overgrowths on existing smaller calcite rhombs. The overgrowths fluoresce a vivid orange color due to slight manganese content. A wonderful and captivating calcite from Naica, of classic habit but in a very large and fine specimen. Complete all around, though sawed on bottom to stand up straight.