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In this study, some Ottoman low carbon steel nails from a 16th century brick masonry dome of Kiliç Ali Pasha Bath in Istanbul and from a 19th century stone dwelling in Phocaea Izmir were studied for their long term corrosion characteristics. Their corrosion layers were examined with a Senterra Bruker micro‐Raman spectrometer and Tescan Vega model Scanning Electron Microscopy (SEM) with Inca X‐Stream 2 Energy‐Dispersive X‐ray spectroscopy (EDX). Powdered samples scraped from the corrosion layers were studied by X‐ray powder diffraction and Fourier transform infrared spectroscopy. The corrosion layer consisted of two main sub‐layers, namely an ‘inner corrosion layer’ including a ‘reaction front’ and a ‘transformed medium’ which included the depositions from the surrounding media. Peak intensities of X‐ray powder diffraction traces were not proportional to the abundance of oxides and oxyhydroxides in the corrosion layer, most probably because of their partly amorphous and nano‐size nature. Inner corrosion layer and transformed medium layers were studied in detail by micro Raman spectroscopy at 532 nm, 0.2 mW, 200 s. The Protective Ability Index (PAI) of the corrosion layers were expressed as the ratio of isotropic goethite band thickness to the thickness of reaction front composed of other oxides and oxyhydroxides being magnetite, maghemite, hematite, lepidocrocite, distinguished by micro‐Raman which is a unique method for phase identification. PAI was then estimated to be ~6–10 for 16th century nails and ~3 for 19th century nails. Corrosion mechanisms and PAI were concluded to be affected by compositional characteristics of artefacts and their atmospheric conditions. Copyright © 2016 John Wiley & Sons, Ltd.

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Ancient stone and brick masonry mortars from three monuments in Konya, Central Anatolia dated to the Anatolian Selçuk Period (12th and 13th centuries AD) were examined for their raw material composition and durability characteristics to understand some characteristics of medieval mortar technology.Optical microscopy, XRD, SEM, EDX, FTIR and TGA analyses revealed that the mortars contained high percentage of lime binder totally carbonated into micritic calcite. Coarse and medium aggregates were mainly composed of sandstone and metamorphic rock fragments, quartz, feldspar and mica minerals. Opal-A was found in considerable amounts in the fine aggregates, likely not derived from the coarser ones but added separately. Pozzolanic activity of the fine aggregates was determined by conductometric measurements. Their ability to form C-S-H was observed by treating them with saturated Ca(OH) 2 solution.Bulk density and total porosity measurements showed that the mortars were highly porous due to the use of high amount of lime. On the other hand, they possessed sufficient mechanical strength. Mechanical properties were determined by point load tests and ultrasonic pulse velocity measurements. They were expressed as uniaxial compressive strength (UCS) and modulus of elasticity (E mod ) in MPa.The results were also discussed in terms of durability characteristics of the mortars. They were expressed with the use of uniaxial compressive strengths in dry and wet states, and total porosity values. The mortars were considered to have high durability to wetting and drying cycles but had poor durability to the crystallization of water-soluble salts.

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