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. 2021 Nov 28;14(23):7290.
doi: 10.3390/ma14237290.

Radiological Hazard Evaluation of Some Egyptian Magmatic Rocks Used as Ornamental Stone: Petrography and Natural Radioactivity

El Saeed R Lasheen  1 , Mohammed A Rashwan  2 , Hamid Osman  3 , Sultan Alamri  3 , Mayeen U Khandaker  4 , Mohamed Y Hanfi  5   6
Affiliations

Radiological Hazard Evaluation of Some Egyptian Magmatic Rocks Used as Ornamental Stone: Petrography and Natural Radioactivity

El Saeed R Lasheen et al. Materials (Basel). .

Abstract

Magmatic rocks represent one of the most significant rocks due to their abundance, durability and appearance; they can be used as ornamental stones in the construction of dwellings. The current study is concerned with the detailed petrography and natural radioactivity of seven magmatic rocks. All are commercial granitic rocks and are identified as black Aswan, Nero Aswan, white Halayeb, Karnak, Verdi, red Hurghada and red Aswan. Their respective mineralogical compositions are classified as porpheritic granodiorite, granodiorite, tonalite, monzogranite, syenogranite, monzogranite and syenogranite. A total of nineteen samples were prepared from these seven rock types in order to assess their suitability as ornamental stones. Concentrations of 226Ra, 232Th and 40K radionuclides were measured using NaI (Tl) scintillation gamma-ray spectrometry. Among the studied magmatic rocks, white Halayeb had the lowest average values of 226Ra (15.7 Bq/kg), 232Th (4.71 Bq/kg) and 40K (~292 Bq/kg), all below the UNSCEAR reported average world values or recommended reference limits. In contrast, the other granitic rocks have higher values than the recommended limit. Except for the absorbed dose rate, other radiological hazard parameters including radium equivalent activity, annual effective dose equivalent, external, and internal hazard indices reflect that the White Halyeb rocks are favorable for use as ornamental stone in the construction of luxurious and high-demand residential buildings.

Keywords: gamma-ray spectrometer; natural radioactivity; ornamental stone; radiological hazard indices.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Distribution map of Neoproterozoic rocks in the Eastern Desert and Sinai after [10], including sample locations over a wide area: (1) black Aswan, (2) red Aswan, (3) Nero Aswan, (4) red Hurghada, (5) yellow Verdi, (6) white Halayeb, (7) Karnak.
Figure 2
Figure 2
Photographs of the examined granitic rocks.
Figure 3
Figure 3
Photomicrographs of the studied magmatic rocks: black Aswan: (a) partially to completely chloritized biotite corroded by undulose quartz and plagioclase; (b) aggregation of titanite associated with plagioclase and titanite. Nero Aswan: (c) slightly sericitized orthoclase perthite corroded microcline and biotite; (d) well developed, euhedral zircon embedded in slightly saussuritized plagioclase. White Halayeb: (e) fine-to medium- grained undulose quartz fractured and filled by sericite; (f) zoned plagioclase engulfing fine-grained quartz. Karnak: (g) euhedral zircon enclosed in microcline, twisted and fractured biotite transformed to chlorite; (h) saussuritized and epidotized pericline plagioclase. Red Aswan: i) very coarse-grained, pristine, patchy microcline engulfing kaolinitized plagioclase; j) coarse-grained allanite surrounded by biotite crystals. Verdi: (k) titanite crystals enclosed by iron oxide, perthite and microcline perthite. Hurghada: (l) extended fracture filled by sericite intersecting extensive saussuritized plagioclase and undulose quartz.
Figure 4
Figure 4
Absorbed dose rate (D), radium equivalent activity (Raeq), external (Hex) and internal (Hin) hazards of the examined samples.
See this image and copyright information in PMC

References

    1. Gaafar I.M., Abdrabboh A., Alshami A.S. Gamma-ray spectrometric investigation of north El-Tor area, southwestern. NRIAG J. Astron. Geophys. 2018;7:390–398. doi: 10.1016/j.nrjag.2018.03.003. - DOI
    1. Rashwan M.A., Lasheen E.S.R., Shalaby B.N. Incorporation of metagabbro as cement replacement in cement-based materials: A role of mafic minerals on the physico-mechanical and durability properties. Constr. Build. Mater. 2019;210:256–268. doi: 10.1016/j.conbuildmat.2019.03.191. - DOI
    1. Hanfi M.Y., Emad B.M., Sayyed M.I., Khandaker M.U., Bradley D.A. Natural radioactivity in the prospecting tunnel in Egypt: Dose rate and risk assessment. Radiat. Phys. Chem. 2021;187:109555. doi: 10.1016/j.radphyschem.2021.109555. - DOI
    1. Stern R.J., Ali K.A., Liegeois J.P., Johnson P.R., Kozdroj W., Kattan F.H. Distribution and significance of pre-Neoproterozoic zircons in juvenile Neoproterozoic igneous rocks of the Arabian-Nubian Shield. Am. J. Sci. 2010;310:791–811. doi: 10.2475/09.2010.02. - DOI
    1. Costa F.P.d., Fernandes J.V., Melo L.R.L.d., Rodrigues A.M., Menezes R.R., Neves G.d.A. The Potential for Natural Stones from Northeastern Brazil to Be Used in Civil Construction. Minerals. 2021;11:440. doi: 10.3390/min11050440. - DOI

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