TUNGSTEN QUEEN MINE TAILINGS EVALUATION, VANCE CO., NC: A POTENTIAL SILICA RESOURCE

The Tungsten (Hamme) Queen mine is located at Tungsten, NC, 16 miles northwest of Henderson, NC, and 2 miles south of the Virginia state line. The ore occurs in a near vertical quartz vein ranging in width from a few inches to several ft. Hübnerite, the principal tungsten mineral, is accompanied by a minor amount of scheelite. Pyrite, the predominate metallic mineral in the quartz veins, is accompanied by subordinate chalcopyrite, galena, sphalerite, and tetrahedrite. Fluorite is a common accessory mineral in the ore and tailings.

Our objective was a preliminary evaluation to produce a high quality quartz concentrate from the approximately 2 million tons of tailings present. Shallow drilling and pits <6 ft deep recovered ~60-pounds of wet tailings from gridded sites on the tailings fan from just below the mill discharge point.

The quartz concentrate was produced using bench scale beneficiation methods including flotation, magnetic, and gravity separation. Size fractions were evaluated for full mineral liberation and non-quartz species using binocular and petrographic microscopes. Quartz analyses were obtained by ICP mass-spectrometry. A concentration flow chart was developed for the heavy and light specific gravity fractions.

Chemical analysis indicates that the quartz may be suitable for fused quartz and silica glass applications. Fluorite comprises up to ~2.5 wt. % of the heavy fraction and is a potential glass flux and other uses. Accessory hübnerite, scheelite, galena, chalcopyrite, and sphalerite may also be recoverable.