CALCITE – AMPHIBOLE – CLINOPYROXENE ROCK
... Na–Ca and Na–Mg–P phases. The very low analytical totals obtained for these minerals using X-ray spectrometry suggest that they contain a significant proportion of CO2 and, possibly, H2O. For all of these minerals, recalculated atomic proportions of cations are nonstoichiometric owing to rapid decom ...
... Na–Ca and Na–Mg–P phases. The very low analytical totals obtained for these minerals using X-ray spectrometry suggest that they contain a significant proportion of CO2 and, possibly, H2O. For all of these minerals, recalculated atomic proportions of cations are nonstoichiometric owing to rapid decom ...
Document (four per page)
... Petoskey stone is a rock, often pebble-shaped, that is composed of a fossilized coral called Hexagonaria percarinata. Petoskey stones are fragments of a coral reef that was originally deposited during the Devonian period, about 350 million years ago. When dry the stone resembles ordinary limestone b ...
... Petoskey stone is a rock, often pebble-shaped, that is composed of a fossilized coral called Hexagonaria percarinata. Petoskey stones are fragments of a coral reef that was originally deposited during the Devonian period, about 350 million years ago. When dry the stone resembles ordinary limestone b ...
CLAY PARTINGS IN GYPSUM DEPOSITS IN SOUTHWESTERN
... Dense, dark finely crystalline dolomite and dolomitic limestone are found above and below the ore bed in both mines. The clay partings are in the upper 1 ft of the gypsum bed and directly below the overlying dolomite. The partings are dark green, olive and dark gray, and range in thickness from a fl ...
... Dense, dark finely crystalline dolomite and dolomitic limestone are found above and below the ore bed in both mines. The clay partings are in the upper 1 ft of the gypsum bed and directly below the overlying dolomite. The partings are dark green, olive and dark gray, and range in thickness from a fl ...
Natural Micron-Scale Roughness of Chemical Sedimentary Rocks
... profiler. To increase reflectivity from the samples, the samples were sputter-coated with a CoCrMoAu alloy. Surface topography was acquired over six separate ~85 x 64 µm areas on each sample, using a step size of ~0.26 µm. Areas of missing data are due to large differences in topography (e.g. “bench ...
... profiler. To increase reflectivity from the samples, the samples were sputter-coated with a CoCrMoAu alloy. Surface topography was acquired over six separate ~85 x 64 µm areas on each sample, using a step size of ~0.26 µm. Areas of missing data are due to large differences in topography (e.g. “bench ...
L6 Mineral Profiles
... make plaster of Paris. Plaster of Paris is used to make casts for broken bones. It can also be used to make statues. This special kind of gypsum is called alabaster and is pink or white. Today gypsum is used to construct wall in homes and buildings. The material known as ‘drywall’ is really ‘gypsum ...
... make plaster of Paris. Plaster of Paris is used to make casts for broken bones. It can also be used to make statues. This special kind of gypsum is called alabaster and is pink or white. Today gypsum is used to construct wall in homes and buildings. The material known as ‘drywall’ is really ‘gypsum ...
Vocabulary for Investigation 2: Scratch Test
... usually fluoresces or glows under an ultraviolet light source. It is used to make high-octane gasoline and as a fluid slag in making steel and smelting other ores. (Hardness = 4) 4) Calcite- another of the most common minerals on Earth. Calcite’s chemical composition is calcium carbonate. Calcite ca ...
... usually fluoresces or glows under an ultraviolet light source. It is used to make high-octane gasoline and as a fluid slag in making steel and smelting other ores. (Hardness = 4) 4) Calcite- another of the most common minerals on Earth. Calcite’s chemical composition is calcium carbonate. Calcite ca ...
Alabaster
Alabaster is a name applied to varieties of two distinct minerals, when used as a material: gypsum (a hydrous sulfate of calcium) and calcite, a carbonate of calcium, also known as onyx-marble, Egyptian alabaster or Oriental alabaster, in geological terms is ""a stalagmitic limestone marked with patterns of swirling bands of cream and brown"". In general, but not always, ancient Alabaster in Egypt and the Near & Middle East is calcite. Alabaster in medieval Europe is gypsum. Modern Alabaster is probably calcite, but may be either. Both are easy to 'work' and as both are slightly water-soluble, have been used for making a variety of indoor artworks and carvings, as they will not survive long outdoors.The two kinds are distinguished from each other readily by differences in their relative hardness. The gypsum kind is so soft as to be readily scratched with a fingernail (Mohs hardness 1.5 to 2), while the calcite kind is too hard to be scratched in this way (Mohs hardness 3), although it does yield readily to a knife. Moreover, the calcite alabaster, being a carbonate, effervesces upon being touched with hydrochloric acid, whereas the gypsum alabaster, when thus treated, remains practically unaffected.The characteristic color of white alabaster has lent its name as a common description of white things, particularly ""alabaster skin"", which means very light and quite translucent, and possibly derives from the use of alabaster for tomb effigies.