Great Chalcopyrite crystals are remarkably rare, these are superb, sharp and quite large. Set on a "melted" Galena matrix with scattered crystals of Sphalerite, the Chalcopyrites are perfect, no chips, cracks or any damage. These have a nice patina and dark brassy color that sets off the well defined striations. Textbook perfect forms these show both single crystals and twins in fine detail. We try to grab any great Chalcopyrite crystals from this region. I believe they are some of the best ever found when they are this well defined. In person this is especially impressive and it is one of the most esthetic we have seen. Individual crystals are just under 5 CM, and the contrast with the matrix is strong. This specimen is also a "floater" it is crystalized all around and displays fine from most any angle.
Chalcopyrite with Quartz
Yaogangxian Mine, Yizhang County
4.3 x 3.8 x 3.1 CM (miniature)
We do not see many good Chalcopyrites from Yaogangxian, although it was a common mineral there. This is an excellent, complete cluster of fine sharp crystals in outstanding condition. Very well defined striations, good patina and esthetic composition, this is all in all a choice piece. For a quite common mineral good Chalcopyrites crystals of this size are rare.
From an older European collection, these are well formed, fine Chalcopyrites with some complex Galena all dusted with Calcites. The original label lists this as from Rodna, but it is unlike any other example we have seen from the locale, and unlike any of the better known Romanian localities (Cavnic, Turt etc). As often happens with old collections we can not always fully trust the locality information, but if correct this is especially fine for the locality and a significant older Roumanian piece with character. Undamaged. The Chalcopyrites reach 2.6 CM and are textbook sharp.
An outstanding cabinet display piece of fine, large (to 4.5 CM) crystals of iridescent Chalcopyrite on contrasting Sphalerite. Although Chalcopyrite is a common mineral, great crystals especially large ones are surprisingly rare. The patina and metallic color play make this especially attractive. An older Casapalca specimen in fine condition overall, with a few small chips mostly on outer edges. As Chalcopyrite is very brittle it is rare to have such large crystals in this fine condition.
A Cornish Chalcopyrite that is well crystallized and with good luster. Sharp trigons to 1.7 CM across are scattered on a thin plate with stained Quartz crystals between each. Ex Huber collection (Austria), in good condition there is some Quartz or Calcite overgrowths on some Chalcopyrites, and Pyrite is present in the matrix.
A delicate and esthetic classic. The early French Creek Chalcos are distinctive and very much sought after, they are definately the most desired US chalcopyrites. The skeletal growth structures make very intricate geometric forms that are well presented here. The enstatite crystals reach 1.6 CM and are all terminated. These make a fine contrast and the overall presentaion is very fine.