Gypsum comes as clear crystals that display one perfect cleavage selenite , as blocks of featureless white rock alabaster , and as silky fibrous blocks satin spar. Halite next page breaks into cubes three cleavages at right angles and tastes like table salt. Go to Halite page. These lab specimens show both distinctive features of gypsum: softness note the white scratches from many finger nails and one nice cleavage plane parallel to ground. Clear crystals or crystal fragments of gypsum are called selenite.
Limestones can also form from the shells of different sea critters that settle out on the bottom of the ocean. So, when we find a limestone, we know that there was a large lake or ocean present at that location in the past. When we find evaporites, we can tell that we were probably in a hot and dry environment such as a desert playa.
Find Your Rock:. Halite, Gypsum Selenite, Limestone, and Limestone with sea creatures. All modern homes in North America and other developed countries use a great deal of wallboard for interior walls. Some gypsum is used to make Portland cement, and some is used in agricultural applications. A small amount of very pure gypsum is used in glass making and other specialized industrial applications.
Skip to content Return to Minerals Database. Related topics: Wonder of Minerals. Industrial Minerals Poster. Cyanobacterial calcification, carbon dioxide concentrating mechanisms, and Proterozoic—Cambrian changes in atmospheric composition Geobiology 4 Precipitation of carbonates by Bacillus sp. Extremely halophilic denitrifying bacteria from hypersaline inland lakes, Halovibrio denitrificans sp. Thompson JB Ferris FG Cyanobacterial precipitation of gypsum, calcite, magnesite from natural alkaline lake waters Geology 18 The Santa Pola saltern as a model for studying the microbiota of hypersaline environments Extremophiles 18 Phototrophic community in gypsum crust from the Atacama Desert studied by Raman spectroscopy and microscopic imaging Geomicrobiol J 30 Biological influences on modern sulfates: textures and composition of gypsum deposits from Guerrero Negro, Baja California Sur, Mexico Sediment Geol An Information-intensive approach to the molecular pharmacology of cancer Science Laboratory simulations of cyanobacterial mats of the alkaline geochemical barrier Mikrobiologiia 72 80 Zimmermann A.
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Sign In or Create an Account. Sign In. Advanced Search. Search Menu. Article Navigation. Close mobile search navigation Article Navigation. Volume Compartmentalization of gypsum and halite associated with cyanobacteria in saline soil crusts. Loredana Canfora , Loredana Canfora. Oxford Academic. Elisa Vendramin.
Livia Vittori Antisari. Giuseppe Lo Papa. Carmelo Dazzi. Anna Benedetti. Pietro Iavazzo. Paola Adamo. Anne D. Flavia Pinzari. Revision received:. Select Format Select format. Permissions Icon Permissions.
Open in new tab Download slide. Table 1. Open in new tab. Table 2. Table 3. Wet crystals. Wet amorphous. Google Scholar Crossref. Search ADS. The micromorphology of gypsum and halite in reg soils—the Negev Desert, Israel. TEM study of a silicate—carbonate—microbe interface prepared by focused ion beam milling. Intracellular Ca-carbonate biomineralization is widespread in cyanobacteria. A likely role for anoxygenic photosynthetic microbes in the formation of ancient stromatolites.
Gypsum and halite associated with the cyanobacterium Entophysalis. Ecology and physiology of phototrophic bacteria and sulfate-reducing bacteria in marine salterns. Microbial mats in the hypersaline ponds of Mediterranean salterns Salins-de-Giraud, France. Gypsum nucleation and crystal morphology in analog saline terrestrial environments. A comparison of calcium sulphate dihydrate growth in clay gels and in sodium silicate gels. Cyanobacterial calcification in modern microbialites at the submicrometer scale.
Comparative analysis of the microbial communities inhabiting halite evaporates of the Atacama deserts. Google Scholar PubMed. Properties, genesis, classification and distribution of soils with gypsum. Characterization of bacterial diversity associated with microbial mats, gypsum evaporites and carbonate microbialites inthalassic wetlands: Tebenquiche and LaBrava, Salar de Atacama, Chile. Microcoleus mats from alkaliphilic and halophilic communities. Biostabilization of cohesive sediments: revisiting the role of abiotic conditions, physiology and diversity of microbes, polymeric secretion, and biofilm architecture.
Cyanobacterial diversity in biological soil crusts along a precipitation gradient, northwest Negev desert, Israel. Metagenomic insights into S 0 precipitation in a terrestrial subsurface lithoautotrophic ecosystem. Extracellular carbonic anhydrases of the stromatolite-forming cyanobacterium Microcoleus chthonoplastes. Molecular diversity of cyanobacteria inhabiting coniform structures and surrounding mat in a Yellowstone hot spring.
Growth of synthetic stromatolites and wrinkle structures in the absence of microbes — implications for the early fossil record. The photosynthetic community of the Trapani saline lagoons: an alternative option for the exploitation of an extreme environment.
Microbial communities and processes within a hypersaline gypsum crust in a saltern evaporation pond Eilat, Israel. Calcification of cyanobacterial filaments: Girvanella and the origin of lower Paleozoic lime mud. Cyanobacterial calcification, carbon dioxide concentrating mechanisms, and Proterozoic—Cambrian changes in atmospheric composition. Evaporitic sedimentation and microbial mats in a salina system Port Fouad, Egypt.
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