Beautiful sand calcite specimen from Spain! Not Hungary; this comes from an unnamed sand pit close to the city of Segovia. Its formation is probably related to the interface between brine and unsaturated water, and unlike many other similar formations, these actually are monocrystalline rather than normal nodules. These appear in a narrow band of sediments and are included with the quartz sand grains of their original host rocks, with some of the more unique examples displaying full pebbles included within.