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John Stewart Vhay

Publications and source records attributed to John Stewart Vhay.

8 recordsLinked to original sources
USGS1960

A preliminary report on the copper-cobalt deposits of the Quartzburg district, Grant County, Oregon

The copper- and cobalt-bearing veins of part of the Quartzburg district are in fracture zones trending about N. 70 degrees E. in folded Permian (?) metavolcanic rocks on the southwest side of a quartz diorite stock. Along many of the veins fine-grained tourmaline and quartz have replaced the country rock. The primary ore minerals are chalcopyrite, glaucodot, safflorite, and cobaltite. The copper- and cobalt-rich parts of the deposits appear to be in separate ore shoots. Gold content is generally higher in the cobalt-bearing parts of the veins than in the copper-rich parts. The Standard mine has developed part of one vein zone. Several other vein zones that crop out may contain as much copper as the Standard vein zone. Further bulldozing and diamond drilling on the surface, and more geologic mapping, sampling, and diamond drilling underground are suggested as means to explore for more ore deposits.

Oregon↗
USGS1958

Minerals of the cassiterite-bearing veins at Irish Creek, Virginia, and their paragenetic relations

Major rock types of the Irish Creek district are gneisses and schists, intruded by granodiorite. All these rocks are believed to be Precambrian. The ore deposits are fissure veins consisting largely of quartz veins bordered by greisen, and enriched by recurrent deposition. From field and microscopic evidence six stages of mineral formation have been deduced: 1. Crystallization of the granodiorite with the formation of hypersthene, augite, hornblende, andesine, orthoclase, microcline, and quartz; and accessory apatite, rutile, ilmenite, titanomagnetite, and zircon. 2. Metamorphism of the granodiorite and gneiss with formation of uralitic actinolite, epidote, and sphene. 3. A period of fracturing and formation of quartz veins. 4. Greisenization of the host rock producing first: coarse muscovite, brown biotite, cassiterite, beryl, wolframite, and quartz; then producing a second group of minerals-fluorite, green biotite, chlorite, phenakite, siderite, ankerite, parisite, sphalerite, sulfides, including aikinite and galeno-bismutite, leucoxene, fine muscovite, and quartz. 5. Formation of late vein minerals, clinozoisite, calcite, nontronite, and montmorillonite. 6. Formation of surficial alteration products, kaolinite, vermiculite, hematite, limonite, and scorodite. The italicized mineral names indicate the minerals heretofore unreported from Irish Creek; parisite, aikinite, and galenobismutite are new minerals for Virginia. Included in the detailed descriptions of all the minerals is a chemical analysis of beryl.

Virginia↗
USGS1951

Reconnaissance examination for uranium at six mines and properties in Idaho and Montana

Six mining properties in Idaho and Montana at which radioactivity had been reported or suspected were briefly examine by J.S. Vhay and W.A. Roberts of the U.S. Geological Survey in October and November 1949. The properties in Idaho are the Grunter mine, from which radio-active mill concentrates have been reported; the Kentuck mine; the Ulysses-kittie Burton Mill; and the Garm-Lemoreaux mine. The properties in Montana are the Armeson-McKenny property in Beaverhead County and the Oro property in Lincoln County. Moderate to high radioactivity was noted at the Garm-Lemoreaux mine and the Armeson-McKenney property. That most of this radioactivity is not caused by uranium is suggested by the low uranium content of the majority of the samples. One sample from a dump of the Garm-Lemoreaux mine assayed 0.11 percent uranium.

Idaho;Montana↗