Mihaela-Lucia Ion

Ceramic Materials Based on Clay Minerals in Cultural Heritage Study

The artifacts belonging to the ceramic heritage are mostly based on all clay types used by humans over the ages, because the sources of clays were easily available and people were interested to produce ceramics and pottery. This is the reason why the conservation of cultural heritage is of great concern. Ceramics (Greek κεράμιον Keramion) is a material obtained by shaping and firing clay. In the Romanian history, many ceramic pieces, of great diversity, have been discovered, and most of them are used in traditional house‐ holds. Ceramic materials based on clay minerals in cultural heritage (ceramic heritage) in‐ volve techniques of characterization of raw materials and ceramic objects based on clays, discovered in different archaeological sites, leading to some results about the production technology, provenance, authentication, and historical appartenance on Romanian terri‐ tory. The chemical composition of ancient ceramics and pigments decorating them, exca‐ vated from different Romanian archaeological sites, suggested a chemical composition of ceramic based on clay minerals (kaolinite, illite, and smectite), while the pigments be‐ longing to them contained red pigments (hematite or ocher), manganese oxides (brown pigments), and magnetite or carbon of vegetable origin (black-pigmented layers).

Nanomaterials and preservation mechanisms of architecture monuments

Knowledge of the chemical composition of the building materials of the monuments may help us to preserve and protect them from the pollution of our cities. The aim of this work is to characterize the materials of the walls from ancient buildings, the decay products that could be appear due to the action of pollution and a new method based on nanomaterials (hydroxyapatite -HAp) for a conservative preservation of the treated walls. Some analytical techniques have been used, as follow: X-ray fluorescence energy dispersive (EDXRF) (for the relative abundance of major, minor and trace elements), FTIR and Raman spectroscopy (for stratigraphic study of cross-sections of multi-layered materials found in wall paintings), Optical microscopy (OM), (for morphology of the wall samples). The nanomaterial suspension HAp applied on the sample surface by spraying, decreased the capillary water uptake, do not modify significantly the color of the samples and induced a reduced mass loss for the treated samples.

Influence of Fântâniṭa Lake (Chalk Lake) Water on the Degradation of Basarabi–Murfatlar Churches

Discovered in 1957, the Ensemble Basarabi–Murfatlar is one of the most impressive archaeological sites from Europe. The monument is situated on a hill chalk cliff, and is built from amorphous calcium carbonate, very sensitive to moisture, frost, salts, as the most important and common causes of monuments degradation. The calcite dissolution is affected by the presence of foreign ions, Mg2+ (from MgSO4 ⋅ 7H2O and MgSO4 ⋅ 6H2O) and Na+ (from Na2SO4 ⋅ 10H2O and Na2SO4), being the major cations in seawater and groundwater. Also, the anions SO 4 2 and Cl− are favouring the calcite conversion to gypsum and is responsible for stone wall dissolution. Some petrographic and physico-chemical (X-ray fluorescence energy dispersive (EDXRF), thermal analysis, ICP-AES of wall samples are presented in this paper. The influence of Fântâniṭa Lake water (Chalk Lake) composition situated very close to the church is discussed, pointing out the salts migration from the lake to the church wall.