Analyses of fluid inclusion gases from Mississippi Valley-type districts in east Tennessee reveal the presence of several distinct aqueous solutions and vapors that were part of the mineralizing process. Inclusion contents were released by crushing 5 to 25 mg mineral samples and by decrepitating individual inclusions; all analyses were obtained by quadrupole mass spectrometry. Most analyzed inc...

Antimony (Sb) is identified as a critical metal in many countries. The source of hydrothermal Sb-bearing deposits currently debated two opposing models (magmatic fluids or country rocks). Some systems host abundant cadmium (Cd). Due to the close association Cd and Sb distinct isotopic signatures between magmatic sedimentary rocks, isotopes have potential trace origin deposits. Here, we conducte...

Reconnaissance geologic investigations by I.L. Tailleur in 1968 noted the presence of widespread iron-oxide staining in creek beds in the Wulik River and Ikalukrok Creek drainages of the western Brooks Range. A brief examination of one of these creeks revealed the presence of weathered sulfide-bearing bedrock and stream sediments containing more than 10 percent lead (Tailleur, 1970). Tailleur n...

The crystal structure of the mineral lautite (copper arsenic sulfide), CuAsS, previously described as either centrosymmetric [Pnma; Marumo & Nowacki (1964 ▶). Schweiz. Miner. Petro. Mitt.44, 439-454] or noncentrosymmetric [Pna2(1); Craig & Stephenson (1965 ▶). Acta Cryst.19, 543-547], was reinvestigated by means of single-crystal X-ray diffraction. The centrosymmetric structural model reported ...

Self-assembly of charged, equally sized metal nanoparticles of two types (gold and silver) leads to the formation of large, sphalerite (diamond-like) crystals, in which each nanoparticle has four oppositely charged neighbors. Formation of these non-close-packed structures is a consequence of electrostatic effects specific to the nanoscale, where the thickness of the screening layer is commensur...