naumannite

naumannite

[′nau̇·mə‚nīt]
(mineralogy)
Ag2Se An iron-black mineral that crystallizes in the isometric system; consists of silver selenide, and occurs massive or in crystals; specific gravity is 8.
References in periodicals archive ?
2 ft of lattice bladed and druzy quartz veining with visible gold and naumannite grading 5.
High grade ore found along this vein is comprised of multi-phase, banded quartz-chalcedony veining with the principal economic minerals consisting of naumannite, pyrargyrite, miargyrite, tetrahedrite, and electrum.
Midas-Style Gold Targets: Mexivada has received assays from 9 new surface rock chip samples taken in 2008 at Goldstorm of Midas-style gold-silver mineralized banded quartz veins that locally have naumannite (silver selenide) interlayered in the bands.
The mineralized zones are marked by banded quartz veins with naumannite (selenium sulphide), bladed quartz with visible gold and naumannite, and brecciation zones with sulphidation and silicification.
This hole intersected four high-grade naumannite banded veins which include: from 1739.
Mexivada recently discovered outcropping high-level Midas-style gold- and naumannite (silver selenide) bearing quartz veining at the surface in silicified/replaced spherulitic rhyolites, which also are found near the top of the Midas Mine gold-silver system.