Ore Grains Research Articles

The origin of thermoremanent magnetization of two basalts containing homogeneous single phase titanomagnetite

Two Tertiary basalts originating from Parkstein and Rauher Kulm, Oberpfalz, Germany, containing almost spherical homogeneous titanomagnetite grains of the same chemical composition (0.65 Fe 2TiO 4 − 0.35 Fe 3O 4) but different grain sizes were investigated with regard to the nature of their thermoremanent magnetization (TRM). In both samples it was found (i) that the TRM component of moderate stability (coercive force <100 Oe) is associated with multidomain grains larger than 1 micron in diameter. The magnitude of this TRM component could be explained quantitatively by the multidomain model of Stacey [3]; (ii) the stable component of TRM could be interpreted with the single domain model of Néel [1] and resides in the particles smaller than 1 micron. The theory of Verhoogen [5] for the stable component of TRM is not relevant for the investigated titomagnetites as the dislocation density in the ore grains was found to be too low (5 × 10 6/cm 2). Electron microscope studies did not show any signs of the “single domain subregions” in the large ore grains as postulated by Ozima and Ozima [6].

Metamorphic aspects of the magnetite-hematite deposit at Benson mines, New York

Garnet, sillimanite, and plagioclase rim and poikiloblastically enclose some iron-oxide and sulfide grains, and iron-oxide grains similarly enclose sulfides. Late sulfides vein silicates, iron-oxides, and early sulfides. Long axes of ovate ore grains tend to lie within biotite-foliation planes, and to be concentrated in the direction of sillimanite lineations. These relationships show that some opaque minerals were present at the time of metamorphism, and are consistent with introduction during or before metamorphism, or even with theirexistence as original syngenetic constituents of the host rocks.

On the Experiment in Surface Changes of Zincblende Ore Grain

Grined zincblende are produced at Budo Mine (Located in Niigata Pref.) was treated in solution reactions upon various pH solutions, and the changes of grain surface was analized in accordance with pH change, wetness, and electropholysis.1. Adsorption of H+ and OH- ion to zincblende are is propotional to the concentration of solution, and are grain itself is changed positive or negative respectivly.2. Adsorption quantity formula : Mz=102.82 | PH-7 |(Adsorption quantity=Mz in unit of 10-7mol, pH=pH of original solution) 3. Adsorption quantity was maximum at the vicinity of 1535°C test condition.4. Fahrenwald's theory is not correct for the adsorption action at 7 of pH, but it is seemed to be correct by some other are grain experiments.5. Adsorption quantities is proportional to electrophysis and degree of wetness.6. Electrophyolysis velocity formula (at 30 volt D. C) : Sz=PH-4/364(Sz=Electrophyolysis velocity, pH=pH of original solution)

Some Experiments on the Heavy Media Separator of New Design

The writers have studied the influence of ore grain size in heavy media separation. The experiments consist of:(1) Sink-float test by the aid of the Acethylentetrabromide as the heavy liquid.(2) Pilot plant test by the aid of the heavy media test separator of new design.The practical data obtained in the heavy media separation tests are given in this report.

Notice of veins of specular iron ore at Strachur, Argyllshire

The upper reaches of Loch Fynne were in past ages of great importance on account of the metals obtained in the district. The very numerous bloomeries which are to be found studded over that part of Argyllshire testify to the importance of the iron industry as carried on in bygone years. The country was especially adapted for the rude but somewhat perfect process used in the older methods for extracting iron from its ores. The steep hill sides afforded capital ground on which to erect the furnace, whilst the oak wood which grew in the immense forests that covered the whole surface of the lower ground, yielded the charcoal necessary for the smelter. So important an element was this wood, that long after the use of the native ores had been discontinued, red iron ore was shipped from Cumberland to Furnace to be worked up into the commercial article. Furnace derives its name from the iron-works which until comparatively lately were in regular work at that place. The native ore of iron which was employed in the manufacture of this Scotch iron is a specular iron ore. It is found in the mica slate in veins, generally in extremely small quantities, and such as at the present high rate of wages renders them commercially useless. They are found in large numbers, and the grains of ore are also distributed through the surrounding rock. You thus find that the houses in the district, and which are built of this mica slate,