Multi‐analytical Studies of Archaeological Chinese Earthen Plasters: The Inner Wall of the Longhu Hall (Yuzhen Palace,Ancient Building Complex,Wudang Mountains,China)

The Yuzhen Palace is one of the nine palaces in the Ancient Building Complex built by order of the Yongle Emperor during the Ming dynasty. The buildings were built with dressed black bricks. As a result of the planned national South–North Water Diversion project, the water level in the Danjiangkou Reservoir that surrounds the Yuzhen Palace was expected to rise by approximately 15 m. To avoid submersion of the site, three gates were elevated by 15 m in 2013 and other buildings dismantled, for later reconstruction. The characterization of the construction materials has therefore become of primary importance. Here, we present results on the plasters of the Longhu Hall. The analysis of materials involved a multi‐analytical approach combining optical and electron microscopy with X‐ray and vibrational spectromicroscopies and thermogravimetry. The results indicated the use of two earthen plaster layers and a whitewash finish coating applied over a thin preparatory intermediate layer to improve the adherence of the finish coating to the earthen plaster. Ramie and straw fibres identified in the earthen plasters were added to reduce shrinkage and cracking during drying. The raw materials used and the application technique pointed to a well‐established construction industry using traditional earthen building materials together with lime technology.     

Characterization of archaeological lime mortars in a Ming dynasty tomb: A multi-analytical approach

Lime mortars have played an important role in constructing ancient Chinese masonry structures, including city walls, buildings, and tombs. A tomb built with lime mortars and stones belonging a Ming high-ranking official, Xu Jie, was discovered in Huzhou City of China. Eight different samples from Xu Jie’s tomb, representing four types of lime-mortar-based materials: joint mortar between stone bricks, bedding mortar, grouting mortar, and plaster mortars were collected for analysis and comparison. The characterization of the construction materials has therefore become of primary importance. The function of each mortar was reported and studies into the micro-textural features and mineralogical compositions of those mortars were performed via a multi-analytical approach. The joint mortars were all found to be aerial lime mortars with predominately lime. The bedding mortar was found to consist of lime, soil and sand, typical of a tabia mortar. The grouting mortar was found to consist of lime and ground contact metamorphosed limestone. Analysis of plaster sample taken from the roof of the main tomb identified the presence of calcium stearate/palmitate, indicating the usage of plant-based tung oil as an additive. The analytical results will promote our understanding of Ming architectural technology and craftsmanship, and provide critical information for the conservation of Xu Jie’s tomb.     

Characterization of ancient building lime mortars of Anhui province,China: A multi-analytical approach

The characterization of lime mortars has become of primary importance in order to obtain information about the raw ingredients and building technology of ancient masonry structures. Five different samples from Anhui province, China, representing two types of lime mortar-based materials: joint mortars between the bricks of the city wall and lime mortar sealing a tomb coffin, were collected for analysis. Archaeological information about the samples was reported and studies into the microtextural features and mineralogical compositions of those mortars were performed via a multi-analytical approach. The joint lime mortars between the bricks of city walls, including Mingzhongdu city wall, Mingzhongdu Xihua gate foundation, Zhengyangguan city wall and She county city wall, were found to be aerial lime mortars. The lime mortar from Nanling Tieguai Song dynasty tomb was analysed and found to be a pozzolanic mortar consisting of lime, clay, sand and cocciopesto-like materials. The analytical results serve as a critical reference for the maintenance and restoration of ancient city walls in Anhui province, and as a starting point for searching for ancient Chinese pozzolanic mortars and technology for making those mortars.     

A Late Roman ceramic production from Pompeii

The Via Lepanto site is one of the best examples showing how the Vesuvian region was partially reconstructed and earlier re-occupied after Vesuvius's eruption in the year 79 AD. The large amount of ceramic finds illustrates the typology in use in this area during the IV and V century AD. Analyses were focused on table and cooking ware productions. Archaeometric data were obtained using chemical and minero-petrographical methods (OM, XRD, XRF and SEM). Grain size measurements using Image Analyses on thin sections and a geochemical comparison with clayey deposits outcropping in the Campania region permitted the identification of the raw materials used for these pottery productions. XRD and SEM completed the data set, establishing the protocols used for pottery production in the Pompeii area during Late Roman period. The Via Lepanto site was part of an exchange network of markets with a periodic frequency, where locally produced and imported pottery was sold, indicating a flourishing network of exchanges spanning short, medium and long distances.