Glauconitic limestone

Krajewski, K. P. (1984). Early diagenetic phosphate cements in the albian condensed glauconitic limestone of the Tatra mountains. Western Carpathians. Chemical Abstracts, 10, 114382. 

Naturally occurring phosphate cements are also known. Krajewski [3] cites calcium-based phosphate cements in the Albeian condensed Glauconitic Limestone of the Tatra Mountains in Western Carpathians. In recent years methods have been developed to fabricate calcium phosphate ceramics by direct reaction of calcium compounds and either phosphoric acid or an acid phosphate. The mineralogy of the products has also been well studied. Most of these efforts are directed towards development of calcium-based bioceramics containing calcium phosphate compounds, such as hydroxyapatite. These developments are discussed below. 

Glauconitic limestone contains glauconite — a hydrated silicate of iron and potassium. 

Cretaceous sedimentation started with the deposition of fresh-water limestones (Hauterivian) followed by successive layers of marine limestones (Barremian), marls (Aptian), marine limestones (Aptian), glauconitic sandstone (Aptian-Albian) and ended with a package of red detritic deposits. 

Raw feed from the southwestern U.S., said to be unusually easy to burn, contains a clayey microcrystalline limestone and shale. The feed has only 3.2% retained on the 125-pm screen, with 15.2% >45 pm, and has <1.0% acetic-acid insoluble residue >45 pm, the latter composed of ordinary quartz with minor amounts of glauconite (a complex alkali-caldum-iron-magne-sium aluminosilicate). Belite nests are scarce and relatively small isolated belite is abundant. The clinker is finely crystalline, easily ground, and produces a high strength mortar (typically greater than 49 MPa). 

Figure 32.6 The ranges of selected brachiopod taxa through the Estonian Ordovician successions preliminary brachiopod associations have been established for the northern belt. I - limestone, 2 - argillaceous limestone, 3 - micritic (aphanitic) limestones, 4 - mainly marls, 5 - clay, 6 - black shale, 7 - sand, 8 - red colouration, 9 - glauconitic ooids, 10 - kukersite above the K-bentonite.

Platform phosphorites are generally nodular, rather than bedded, and are associated with sandstone, limestone and glauconite. Most are low in uranium, but an exception is the Bone Valley Formation of the southeastern U.S.A. This unit has been reworked and enriched by re-exposure to sea water during a subsequent transgression. These phosphorites differ from shelf phosphorites in that they are near-shore sub-tidal and shoreline deposits, and they change facies oceanward to carbonate sediments. 

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