ORPIMENT
Specimen orp-5
$ 81.00Dims: 4.0 x 3.8 x 2.4" (10.2 x 9.7 x 6.1 cm)
Wt: 12.5 oz. (354 g)
Quiruvilca, La Libertad Department, Peru
This hand specimen consists of several Orpiment crystals that rest on a pyrite-laden host rock. A few of the crystals are damaged, but most appear to be in good condition. I believe that none of them exceed 0.8" (2.0 cm) along their longest axis. It is difficult to gauge their size or study their crystal form, as all are covered with a 0.1" (3 mm)-thick crust that is made up of thousands of other, tiny Orpiment crystals (see the second image). Several very exposed areas of this crust are visibly damaged due to crushing, but otherwise it is in good condition. It has a dark yellow-orange coloration and an almost silky luster, whereas the larger crystals beneath it are brighter in color and have a pearly luster. The Orpiment rests on what appears to be a thin layer of white crystalline calcite sandwiched between it and the host rock. I think that this Orpiment specimen is one of the most interesting that I have ever seen.