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C. Milton

Publications and source records attributed to C. Milton.

12 recordsLinked to original sources
USGS2018

Dwornikite, (Ni,Fe)SO 4 .H 2 O, a member of the kieserite group from Minasragra, Peru

A new nickel sulphate monohydrate is described from V-sulphide ore from Minasragra; it occurs associated with patronite (VS 2 ) with various sulphates, sulphur and bitumen. Dwornikite forms fine-grained white aggregates mixed with other oxidation products. Indexed X-ray powder data are tabulated; strongest lines 3.342(100) , 4.732(70), 3.024(70), 4.754(50), 3.293(35), 2.491(35) A; a 6.839, b 7.582, c 7.474 A, beta 117.85o; space group C2/c. XRF gave NiO 39.0, FeO 9.3, SO 3 42.4, = 90.7; D calc. 3.34 g/cm 3 ; mean refr. ind. approx 1.63. Unit-cell data for the synthetic end-member compounds NiSO 4 .H 2 O and FeSO 4 .H 2 O and new X-ray powder data for retgersite (NiSO 4 .6H 2 O) are given. The name is for E. J. Dwornik, mineralogist with the U.S. Geological Survey.-R.A.H.

Mineralogical Magazine↗
USGS2014

Diabase dikes of the Franklin Furnace, New Jersey, quadrangle

Two of the numerous small dikes mapped on the areal geology sheet of the Franklin Furnace Folio (U.S. Geological Survey 161) as “Mostly basic, including nepheline tinguaite, leucite tinguaite, and camptonite” of post‐Ordovician age, have been found to be quite distinct from these alkalic rocks, and the two dikes in question are indistinguishable from the Triassic diabase found elsewhere in New Jersey and adjoining States. The association of diabase with highly alkalic rocks has been observed and commented on by numerous writers. There is evidence pointing to the post‐Triassic age of the Beemerville alkaline rocks, and a possible correlation with a volcanic ash of Cretaceous age found by Stephenson and Carter at Haddonfield, New Jersey, near Camden, in 1936. ©1938. American Geophysical Union. All Rights Reserved.

New Jersey↗
USGS1969

Merumite occurrence in Guyana

Merumite was discovered with associated diamonds and gold in 1937 in gravels of the Merume River in Guyana. It was described as essentially a hydrous chromium oxide that contains more than 80 percent Cr2Oa. Milton and Chao in 1958 found it to be a complex aggregate, mainly eskolaite (Cr2Oa) with five or more new chromium minerals which have recently been identified. The deposit is unique. The richest gravel, averaging several ounces merumite per cubic yard, extends about 2 miles along the base of an east-dipping (35°) ridge of sandstone and ash beds, perhaps an outlier of the Precambrian Roraima Formation that forms bold mountainous scarps a few miles south. No chromium mineralization has been observed in the ridge or anywhere in the region, other than the merumite in the placer gravel. Merumite commonly occurs as grains a few millimeters across, but specimens as large as 10 cm have been found. Almost all the merumite is in rounded grains, many with broken worn edges, indicating wear in transport. Granular gold is enclosed in merumite, as is chromian pyrophyllite. Many merumite grains have impressions, and some contain crystals, of doubly terminated "needle" quartz. Water-worn gorceixite, rutile, tourmaline-quartz fels, jasper, euhedral glassy quartz (as much as several centimeters long), and fragments of basaltic rock accompany merumite at all localities; rarely, gold and diamonds are associated in the placers. Merumite was probably derived from a local moderate-temperature hydrothermal deposit possibly formed in the adjacent sandstone-volcanic ash bed from solutions related to local ash deposits and massive gabbro-dolerite intrusive bodies in the Roraima Formation. If the deposit was formed at depths of less than a few thousand feet, erosion may have reached it and re-deposited the merumite and accompanying resistant minerals, mostly'quartz and jasper, in local stream beds. © 1969 Society of Economic Geologists, Inc.

Merume River↗
USGS1966

Dawsonite in the green river formation of Colorado

Dawsonite NaAl(OH)2C03 is a rare mineral that occurs in relative abundance over hundreds of square miles in the Piceance Creek Basin of northwestern Colorado, as a rock-forming constituent of the oil shales in the green River Formation. In some specimens it makes up 25 percent by weight of the shale. Containing 35 percent of acid-soluble A1203, it has been viewed as a potential ore of aluminum. The dawsonite extends through 700 feet of continuous section of high-grade oil shale (averaging 25 gallons per ton), which may be as much as 1,500 feet in thickness. Its distribution, areally and stratigraphically, is reviewed; methods for its identification, and for its quantitative determination in the oil shale, with special reference to X-ray diffraction procedures are described; and the geochemistry of dawsonite, as it relates to the origin of the mineral, is considered. The scattered literature on dawsonite is briefly summarized. © 1966 Society of Economic Geologists, Inc..

Colorado↗
USGS1958

Nickel-gold ore of the mackinaw mine, Snohomish County, Washington

The Mackinaw mine ore is of an unusual or unique type, consisting chiefly of niccolite, maucherite, pentlandite, chalcopyrite, cubanite, and magnetite in an altered peridotite. Valleriite, gold and sphalerite are minor primary minerals; chalcocite and violarite or bravoite are supergene minerals. Pyrrhotite and pyrite are absent. From the textural relations it is inferred that a complex copper-nickel-iron sulfide was deposited early. On cooling, the sulfide unmixed into two different complex sulfides, one of which in turn unmixed into chalcopyrite and cubanite, the other into chalcopyrite and pentlandite. The latter exsolution relationship has not been previously reported. Valleriite either exsolved from, or replaced, chalcopyrite. Late solutions altered the niccolite to maucherite, and introduced gold and magnetite. The gold is almost always with maucherite.

Washington↗
USGS1958

Metamorphosed middle Paleozoic fossils from Central Massachusetts, eastern Vermont, and western New Hampshire

Study of thin and polished sections and spectrographic analyses indicate that the brachiopod most recently used to date the Bernardston Formation in Massachusetts probably came from Lower Devonian beds (chlorite zone) in Nova Scotia, and not from Bernardston, Massachusetts. Restudy of the faunule from the calcareous quartzite (garnet zone) of the Bernardston Formation indicates that it is probably of Silurian rather than Devonian age. The upper part of the Clough Formation on Skitchewaug Mountain (garnet zone) in eastern Vermont contains tetracorals of Silurian or Devonian age. The Clough Formation on Croydon Mountain (sillimanite zone) in west-central New Hampshire contains tetracorals. The fossiliferous zone in the lower part of the Bernardston Formation is possibly equivalent to the upper part of the Clough Formation.

Vermont, New Hampshire, Massachusetts↗
USGS1955

Sub-chattanooga residuum in Tennessee and Kentucky

Between the Chattanooga shale and the underlying limestone in parts of Tennessee and Kentucky is a clayey gray to brown zone as much as several feet thick. This represents an interval of limestone that has been leached by sulfuric acid formed by oxidation of the abundant pyrite in the black shale. Alteration of the limestone decreases with distance from the base of the black shale; several stages of alteration are recognized and described. The acid also attacks the shale, as indicated by locally conspicuous efflorescences of copiapite, coquimbite, halotrichite, gypsum, and possibly other sulfates. Basaluminite, a hydrous aluminum sulfate previously reported only from England and France, was found in geodal cavities and thin seams in the residuum. The clayey zone has been previously interpreted as an ancient soil formed on the limestone surface during Devonian time. Petrography and chemical composition of the leached zone are described and illustrated by photomicrographs. The nature of the shale-limestone contact where the leached clayey zone is absent is illustrated by a diamond-drill core from Tennessee. Many fresh outcrops and several dozen cores that penetrate the contact show no clayey material at this position. The clayey zone does not represent an old soil. © 1955, The Geological Society of America, Inc.

Tennessee, Kentucky↗
USGS1953

Reconnaissance of superficial phosphate deposit near Minas, Uruguay

The phosphate deposit in Uruguay described here is of interest primarily because it is believed to be a superficial deposit that resulted from the action of guano on volcanic rock. Even though some of the rock contains as much as 30 per cent P206, it is unavailable as a source of fertilizer because the phosphate is combined with aluminum and iron as variscite and strengite, and possibly other equally insoluble minerals. © 1953 Society of Economic Geologists, Inc.

Economic Geology↗
USGS1938

Sulphate minerals of the Comstock Lode, Nevada

Seventeen representative samples of supergene sulphates from old workings on the Comstock Lode are described. They range from simple minerals such as gypsum and epsomite to complex aggregates of four or more distinct species. All are well known species except a mineral of the copper (chalcanthite) or magnesium sulphate pentahydrate group, with about half the magnesium replaced by copper, zinc, ferrous iron, and manganese. Four new analyses of Comstock Lode mine waters are given. © 1938 Society of Economic Geologists, Inc.

Nevada↗