Arsenic Family Minerals-Part II:Erythrite, Realgar, Orpiment and Scorodite Add Rich Color to a Collection

摘要

One place in which smears of realgar and orpiment are encountered is the old dumps of the great borate deposits in Boron, California. There is plenty of evidence of ancient volcanic activity here. It is not unusual to see evidence of realgar and more often orpiment on specimens of ulexite, coleman-ite, and so on. The great Yellowstone Park area, which is one of the most active volcanic regions in our country, has countless active hot springs and is a near-surface volcanic site. Evidence of these two minerals, along with yellow sulfur, is found throughout the park.