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Jewell J. Glass

Publications and source records attributed to Jewell J. Glass.

6 recordsLinked to original sources
USGS2014

Rare chemical constituents of amelia (Virginia) pegmatite dikes, and their mineral sources

Students of Igneous phenomena have long since become familiar with the occurrence of rare minerals in pegmatitic bodies. The great local concentration of rare elements in pegmatite minerals provides a remarkably good opportunity for the Investigation of deep-seated rock constituents, for it is reasonable to suppose that these same elements are widely distributed in minute amounts through the parent rocks to which they are genetically related; but their concentration in pegmatite bodies affords a record of their presence that is lacking in other rocks. The unusual number of rare minerals of the Amelia, Virginia, pegmatites has long attracted attention, and the rare elements of the more abundant minerals which have been investigated in the laboratories of the United States Geological Survey afford an unusual opportunity to study the rare constituents of a pegmatite. This famous locality for rare minerals is situated 38 miles southwest of Richmond, just south of Appomattox River, on the Piedmont plateau.

Eos, Transactions, American Geophysical Union↗
USGS2014

Extraordinary topaz‐replacement body in the Brewer Mine, South Carolina

A large body of massive topaz forms a part of the gold‐bearing lode at the Brewer Mine, South Carolina. This gold‐mine was opened 100 years ago and merits the distinction of being one of the early gold‐discoveries of the Southern Appalachian Region. The Brewer Mine is located near Jefferson, in Chesterfield County, near the northern boundary of South Carolina, and on the eastern edge of the Piedmont Province. The country rock is described by J. T. Pardee and C. F. Park, Jr., (Gold‐deposits of the Southern Appalachians, U. S. Geol. Surv. Prof. Paper, in preparation) as a quartz‐sericite schist that locally preserves the structure of a fine‐grained, waterlaid tuff, probably a rhyolite,from which it was derived. Exposures of granite that intrude the schist appear on the north and west at distances of a mile to a mile and a half.

South Carolina↗
USGS2014

Helvite, a product of magmatic emanations at Iron Mountain, Sierra Socorro Counties, New Mexico

The recent discovery of the widespread occurrence of helvite, a beryllium‐bearing mineral, at Iron Mountain, New Mexico, has aroused interest in the commercial possibilities of a mineral which heretofore has been considered to have only scientific significance. Helvite contains about 13 per cent beryllium oxide as compared with five to ten per cent beryllium oxide in the mineral, beryl, which at present is the principal source of commercial beryllium. Helvite is consistently distributed, though sparingly in some places, through great masses of contact‐metamorphic rock at Iron Mountain and, therefore, provides great hope for the future when the metallurgical problems have been solved and large‐tonnage, low‐grade ore can be utilized.

New Mexico↗
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↗