Definition of calcitic in US English:



  • See calcite

    • ‘Some of the most attractively preserved fossils are the yellow and brown calcitic moulds of ammonites that are characteristic of calcareous concretions.’
    • ‘Like all echinoderms, echinoids are pentaradially symmetrical, have a water-vascular system, and have an internal skeleton made of calcitic ossicles (plates).’
    • ‘The Atlantic and Gulf Coastal Plains of the United States contain assemblages preserved as original aragonitic and calcitic material in unconsolidated sediments.’
    • ‘All tyrannosaurid and hadrosaur bones lie horizontally within a 20 cm thick blocky, green claystone with occasional calcitic nodules and vertical to subvertical burrows.’
    • ‘The calcitic ossicles of crinoids, as is typical of echinoderms, form an internal skeleton that provides support and protection.’
    • ‘At most localities, only the outer prismatic calcitic shell layer is preserved, although some specimens retain the recrystallized inner shell layer.’
    • ‘Modern pinnids are morphologically and microstructurally nearly symmetrical, with the same calcitic regular simple prismatic structure comprising a layer of similar thickness in the left and right valves.’
    • ‘The remaining carbonate bioclasts are exclusively calcitic echinoid spines, rare foraminifera, molluscs and bryozoan fragments.’
    • ‘The formerly aragonitic specimens are preserved as moulds and the calcitic faunal elements are usually partly decalcified.’
    • ‘The original composition of many early Cambrian small Problematica occurring as phosphatic fossils is still uncertain, with many authors invoking widespread diagenetic replacement of calcitic material by phosphate.’
    • ‘Having a thick, amorphous, calcitic layer of shell material, these gastropods stood a better chance of preservation than other groups of mollusks that obviously must have shared their geographic distribution throughout the Tertiary.’
    • ‘Remnants of outer calcitic shell layer show a polygonal pattern indicating original presence of columnar prismatic structure; inner aragonitic layers not preserved.’
    • ‘In Conchicolites the vesicular shell structure is absent and the calcitic prisms are deposited at the shell aperture more or less at right angles to the longitudinal shell axis.’
    • ‘The generic assignment remains questionable, however, because right valves are unknown, and because the specimens appear to lack the prismatic and crossed-foliated calcitic microstructures that are broadly present in the family.’
    • ‘The largely foliated calcitic shell microstructure of true oysters, once taken as a strong indication of a pectinoid relationship, evolved independently of that of pectinoids, as indicated by Carter.’
    • ‘Concretions, which were originally calcitic, are either weathered out or now contain epidote as a cement.’
    • ‘Both specimens retain their original calcitic outer shell layer, original aragonitic middle and inner shell layers, and remnants of aragonitic ligament fibers.’
    • ‘The arms of ophiuroids and crinoids (phylum Echinodermata) are supported by calcitic ossicles reminiscent of vertebral centra.’
    • ‘The specimens are preserved as mostly fragmental, three-dimensional, fully to partially testiferous, internal molds formed as, or in association with, sideritic or calcitic concretions.’
    • ‘At Lawson Cove there are many collections that yielded trilobites, conodonts, organophosphatic brachiopods (this report), and calcitic brachiopods, but no graptolites.’