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Microplastics (MPs) have been found in marine systems more frequently. We aim to analyze the MPs abundances, distribution, and characteristics in the intertidal sediments along the Oman Sea. Samples were collected from 7 locations with three replicates. Density separation was used to extract MPs, which were then visually counted and categorized based on their size, shape, and color. MPs abundance ranged between 219.6 ± 38.3 particles.kg−1dw and 617.3 ± 99.9 particles.kg−1dw with a mean abundance of 315.4 ± 24.4 particles.kg−1 dw. Fragments and fibers were the dominant shapes. Red and blue colors were observed in 61.6 % of the collected MPs. In addition, 100–500 μm size range of MPs were more abundant. Micro-Raman spectroscopy analysis revealed polypropylene was the major polymer constituent. The present study revealed the widespread occurrence of MPs as anthropogenic pollutants throughout the Oman Sea and highlighted the urgent need for regulations and policies to reduce the entry of this material into marine environments. [Display omitted] • Baseline information of MP abundance in the intertidal sediments along the Oman Sea was documented for the first time. • Microplastics were ubiquitous in the surface intertidal sediments along the Oman Sea. • Fragments and fibers were the most abundance shapes of microplastics. • Polypropylene was the major polymer constituent in the samples. [ABSTRACT FROM AUTHOR]

The present paper aims to characterize some Roman plasters from the reign of the Emperor Diocletian in the late 3rd century AD. These plasters were applied over Pharaonic walls from the reign of Amenhotep III (c.1402-1364 BC) at Luxor temple, Upper Egypt. For the characterization of theses plasters, several analytical techniques were applied such as optical microscopy (OM), scanning electron mi-croscopy (SEM) equipped with an energy dispersive X-ray detector (EDS), X-ray powder diffraction analysis (XRPD), micro- Raman and Fourier transform infrared spectroscopies (µ-Raman and FT--IR). Based on the results of these analyses, the stratigraphic structure of the plaster layers was identified as fine coat 'intonaco' which is based mainly on lime and coarse coat 'arriccio' which consists of silica sand, phases of calcium carbonates and different pozzolanic additives. Moreover, the results revealed the green pigment as green earth (celadonite), the red pigment as red ochre, the yellow pigment as yellow ochre and the white pigment as cal-cium carbonate. The obtained data helped in improving our knowledge of some materials used during the Roman age in Egypt. [ABSTRACT FROM AUTHOR]