
Occurrence. Gypsum is a common mineral, with thick and extensive evaporite beds in association with sedimentary rocks. Deposits are known to occur in strata from as far back as the Archaean eon. Gypsum is deposited from lake and sea water, as well as in hot springs, from volcanic vapors, and sulfate solutions in veins.

A variety of Gypsum The name 'selenite' is mostly synonymous with gypsum but has been used historically to describe the transparent variety, as opposed to satin spar gypsum for the fibrous variety and alabaster for the fine-grained massive form. The original name was given by J.G. Wallerius in his 1747 book "Mineralogia, eller Mineralriket" (p.50), as 'selenites'.

Sustainability of gypsum products as a construction material 661 compressive strength of foam gypsum specimens with an av erage density of 600 kg/m 3 in dry state is between 1.5 and 2.5 MPa, when

Iron ore production in Africa is dominated by South Africa, Mauritania and Algeria. Many countries possess iron ore deposits that are as yet untapped/unmined. Many countries possess iron ore deposits that are as yet untapped/unmined.

Gypsum occurs in nature as flattened and often twinned crystals, and transparent, cleavable masses called selenite.Selenite contains no significant selenium; rather, both substances were named for the ancient Greek word for the Moon.. Selenite may also occur in a silky, fibrous form, in which case it is commonly called "satin spar".


A not-for-profit trade association founded in 1930, promoting the use of gypsum while advancing the development, growth, and general welfare of the gypsum industry in the United States and Canada on behalf of its member companies

Occurrence. Gypsum is a common mineral, with thick and extensive evaporite beds in association with sedimentary rocks. Deposits are known to occur in strata from as far back as the Archaean eon. Gypsum is deposited from lake and sea water, as well as in hot springs, from volcanic vapors, and sulfate solutions in veins.

This page contains all mineral locality references listed on mindat. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only.

Circumgranular bassanite in a gypsum crust from eastern Algeria A potential palaeosurface indicator Article in Sedimentology 50(6):1139 1145 · November 2003 with 19 Reads How we measure 'reads'

Gypsum is a very common mineral; only a select few of the best and most classic are mentioned here. The finest European localities are Lubin, Poland; Kapnick, Maramures Co., Romania; and the Sulfur mines of Agrigento Province, Sicily, Italy. Desert Roses and Sand Gypsum come from several places in the Sahara Desert in Algeria and Morocco. Excellent Gypsum specimens have come from China at

Occurrence. Gypsum is a common mineral, with thick and extensive evaporite beds in association with sedimentary rocks. Deposits are known to occur in strata from as far back as the Archaean eon. Gypsum is deposited from lake and sea water, as well as in hot springs, from volcanic vapors, and sulfate solutions in veins.

Nigeria also has other resources useful for energy and construction, including a poorly understood lignite belt in the south, kaolin, gypsum and feldspar. Coal mining provided much of the country's energy between 1915 and 1960, although the industry has been in a long-running decline, now providing energy only for small-scale kilns and smelters.

Gypsum occurs in nature as flattened and often twinned crystals, and transparent, cleavable masses called selenite.Selenite contains no significant selenium; rather, both substances were named for the ancient Greek word for the Moon.. Selenite may also occur in a silky, fibrous form, in which case it is commonly called "satin spar".

Global Journal of Pure and Applied Sciences. Home; Current Archives About About the Journal Home Archives Vol 6 No 2 (2000) Articles Earth Sciences Occurrence, geochemistry and origin of gypsum deposit in Nafada, Gombe State, Nigeria. J M EL-NAFATY A A EL-NAFATY DOI: 10.4314 /gjpas.v6i2.16115 Algeria (5) Benin (1

The uses and properties of the mineral Barite. Barite Occurrence. Barite often occurs as concretions and void-filling crystals in sediments and sedimentary rocks.It is especially common as concretions and vein fillings in limestone and dolostone.Where these carbonate rock units have been heavily weathered, large accumulations of barite are sometimes found at the soil-bedrock contact.

The Arabic expressions for salt (melah) and gypsum (zebs), frequently used in local geographic descriptions, draw attention to the widespread occurrence of evaporites in North Africa. The principal occurrences consist of variegated red clay containing gypsum and salt alternating with limestone, dolomite, breccia, and cellular dolomite.

Naturally Occurring Radioactive material, natural materials contain radioactive elements (radionuclides), known as NORM. The earth's crust is radioactive. Information from the World Nuclear Association, the global private-sector organization that seeks toprovide information on nuclear power, nuclear energy, Chernobyl, uranium, nuclear waste management.

Hematite is dense and hard, it is the most important ore of iron because of its high iron content and its abundance.The mineral occurs in various habits: steel-gray crystals and coarse-grained varieties with a brilliant metallic luster are known as specular hematite; thin, scaly forms make up micaceous hematite; and crystals in petal-like arrangements are called iron roses.

Occurrence: In Algeria (Oued Takouazet, Tinrhert area), R. alatus is ranging from the upper Cenomanian carbonates (Vascoceras limestones with V. gamai Choffat and Vascoceras sp., coeval to the Neocardioceras juddii Zone) to the lower Turonian (limestone bed delivering Pseudotissotia nigeriensis [Woods], coeval to the upper part of the

· Gypsum rock is mined or quarried, crushed and ground into a fine powder. In a process called calcining, the powder is heating to approximately 350 degrees F, driving off three fourths of the chemically combined water. The calcined gypsum, or hemihydrate, becomes the base for gypsum plaster, gypsum board and other gypsum products. Get More

AVOIDING GYPSUM GEOHAZARDS: GUIDANCE FOR PLANNING AND CONSTRUCTION A €-I Cooper’ and R C Calow? BGS Central England and Wales Group’ and Hydrogeology Group’ This report is an output from a project funded by the UK Department for International Development (DFID) under the UK provision of technical assistance to developing countries.

In its pure form gypsum is white, a chalk like material but in combination with impurities, it may be gray, brown or pinkish. Relatively pure calcined gypsum is known as Plaster of Paris, after the huge beds of it that underlie the city of Paris where it was mined in abundance in the

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The uses and properties of the mineral Barite. Barite Occurrence. Barite often occurs as concretions and void-filling crystals in sediments and sedimentary rocks.It is especially common as concretions and vein fillings in limestone and dolostone.Where these carbonate rock units have been heavily weathered, large accumulations of barite are sometimes found at the soil-bedrock contact.

Dunes are large masses of wind-blown sand, and are most common in deserted environments, such as the Sahara, and also near beaches.An area with dunes is called a dune system. In physical geography, a dune is a hill of loose sand built by aeolian processes (wind) or the flow of water. Dunes occur in different shapes and sizes, formed by interaction with the flow of air or water.

Occurrence. Gypsum is a common mineral, with thick and extensive evaporite beds in association with sedimentary rocks. Deposits are known to occur in strata from as far back as the Archaean eon. Gypsum is deposited from lake and sea water, as well as in hot springs, from volcanic vapors, and sulfate solutions in veins.

Salt-affected soils generally occur in regions that receive salts from other areas and water is the primary carrier. Although the weathering of rocks and minerals is the source of all salts, rarely are the salt-affected soils formed from the accumulation of salts in situ. 2.2 Classification

Ground Water Contamination with Fluoride and Potential Fluoride Removal Technologies for East and Southern Africa, Perspectives in Water Pollution, Imran Ahmad and

Occurrence. Taranakite was first described in 1866 by James Hector and William Skey. The material had been found by H. Richmond on the Sugar Loaf Islands of Taranaki, New Zealand (in the vicinity of ), as thin yellowish-white amorphous seams in fissures within trachytic Within the taranakite, dark yellow-brown seams were observed and thought to be wavellite.

Africa Africa Metallic deposits: In North Africa reserves of iron ore are concentrated in the Atlas Mountains and in the western Sahara. Egypt, however, has medium-grade reserves, of which the most important are at Al-Baḥriyyah Oasis. The ore deposits in Morocco and Tunisia, which were once of considerable importance, have been severely depleted. Africa’s most significant iron reserves

Jul 11, 2018· Climate change is having short- and long-term impacts on surface and groundwater in the northern part of the African continent. This has led to a wide range of consequences that have added pressure on the groundwater systems in this part of the world. Among such pressures, we can cite the mal-distribution and the irregularity of precipitation and ice, flooding, evaporitic sediments input by

Lime production begins by extracting limestone from quarries or mines. PRODUCTION PROCESS Made from high quality, natural deposits of limestone, and meeting exacting chemical and physical properties, NLC has a broad range of lime

gypsum, dolostone, and mudstone, called the Saliferous Units (fig. 5) (Bishop, 1975). These rocks form a regional seal for many oil and gas reservoirs (van de Weerd and Ware, 1994). The sequence is thickest near the Saharan Flexure in the north, and it thins southward. The combined maximum thickness (Triassic and Jurassic sections) exceeds

Gypsum is a very common mineral; only a select few of the best and most classic are mentioned here. The finest European localities are Lubin, Poland; Kapnick, Maramures Co., Romania; and the Sulfur mines of Agrigento Province, Sicily, Italy. Desert Roses and Sand Gypsum come from several places in the Sahara Desert in Algeria and Morocco. Excellent Gypsum specimens have come from China at

The Arabic expressions for salt (melah) and gypsum (zebs), frequently used in local geographic descriptions, draw attention to the widespread occurrence of evaporites in North Africa. The principal occurrences consist of variegated red clay containing gypsum and salt alternating with limestone, dolomite, breccia, and cellular dolomite.

Sand dune, any accumulation of sand grains shaped into a mound or ridge by the wind under the influence of gravity. Sand dunes are comparable to other forms that appear when a fluid moves over a loose bed, such as subaqueous “dunes” on the beds of rivers and tidal estuaries and sand waves on the

Sep 17, 2019· 1 INTRODUCTION. Lygeum spartum is a robust rhizomatous grass, which is widely distributed in the Mediterranean region. It belongs to the subfam. Pooideae and it is the only representative of the tribe Lygeeae (Soreng et al., 2015). Lygeum spartum occurs from sea level up to an elevation of 2,260 m, mainly in the Western Mediterranean (Iberian Peninsula, NW Africa), with some
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