![]() The paper reports the results of a multi-analytical characterization study on the renders constituting the waterproofing coatings of 11 cisterns located in the Punic-Roman archaeological site of Nora (Southern Sardinia, Italy). In the meantime, the experimental mixing and tempering of locally sampled raw materials have shed light on the ancient manufacturing process and have led to an approximation of the original paste. Furthermore, the physical properties of this ceramic type have been defined in order to better understand its performance characteristics, mainly in response to induced thermal stress. Using a representative number of samples of Pantellerian ware that were recently discovered in the island through archaeological field surveys or surface and submarine excavations, it was possible to characterize in detail the compositional variability of this ware in terms of chemistry and petrography. The present paper is a comprehensive review of this archaeometric work and aims to establish a ‘reference group’. Recurrent ceramic forms, their distribution over time and space, their petrographic characteristics and their chemical identity, as well as possible raw materials and their technological properties, were considered. Archaeological and archaeometric studies carried out by the authors of the present contribution during the past four years have aimed to fully characterize this ceramic class. Pantellerian ware is a Late Roman cooking ware whose production centre was established on the island of Pantelleria by the pioneering research of Fulford and Peacock almost 20 years ago (Peacock 1982 Fulford and Peacock 1984). It was found that the average Ca 2+ concentration and EC value in rinse solution fit approximately 90% with RSM predicted data. The accuracy of the modeling was validated with triplicate experiments. The experimental results revealed that desalination process in optimized conditions results in speed up the operation time up to less than 8% and saving up to 50% water consumption compared to conventional method at the same desalination achievement. It was found that the most effective parameters in the immersing desalination process are: firing temperature of specimen, immersing time, and agitation rate. Electrical conductivity (EC) and Ca 2+ concentration of rinse solutions were measured as responses of experiments. ![]() For each variable, five levels were selected in a batchwise pilot tests. ![]() ![]() The input (independent) variables in the experimental design were immersing time, agitation rate, firing temperature (as void fraction indicator), type and concentration of surfactant. As this process is a multivariable system, a new approach based on a mathematical design of experiment, response surface methodology (RSM), was used as a n aid in determining the significance of the various parameters and optimization of this process. On the other hand, a considerable amount of water is used in this process because of a huge number of excavated potteries in archaeological sites, therefore, controlling the amount of rinse water consumption is extremely desirable. Since this process is irreversible, and object has direct vicinity with water, preventing the misrepresentation of valuable archaeological and archaeomet-rical data of historic object will be substantial. potteries, bricks, etc.), desalination is highly important process in conservation. As salt crystallization is one of the most serious damages in historical porous materials (e.g.
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