Abstract - Vol LXXVIII, Septmber 2009 n. 2

- Ankangite from the Monte Arsiccio mine (Apuan Alps, Tuscany, Italy): occurrence, crystal structure, and classification problems in cryptomelane group minerals.

- A new occurrence of ankangite, a rare member of the hollandite structural family, is described. Ankangite was found in small fractures in dolomitic marble at the Monte Arsiccio mine, a small deposit of baryte, pyrite and Fe oxides in the Apuan Alps, Tuscany, Italy. The mineral occurs as prismatic black crystals, up to 5 mm in length, associated with “apatite”, anatase, arsenopyrite, Ba-rich K-feldspar, baryte, dolomite, pyrite, quartz, sphalerite, stibnite, valentinite, and zinkenite. The crystal structure of ankangite from the Monte Arsiccio mine was refined to R₁ = 0.016. Ankangite is a member of the titanate subgroup in the cryptomelane group. The classification and nomenclature of the hollandite-group minerals are discussed.

- Mineralogical-petrographic characterisation and provenance of “Porta Nuova” stones: A XVI century gate in Ravenna (Italy).

- Porta Nuova in Ravenna (Northern Italy) is one of the most beautiful gates of ancient Ravenna walls, built in the XVI century (1580-1585).Through the centuries, the door underwent several restoration events, the most important in 1653. a recent architectural survey has revealed that the Door is currently undergoing both structural deterioration and bad conservation of stone materials. Therefore, the Door has been subjected to laboratory investigation for the purpose of collecting data useful for restoration. This work presents a detailed mineralogical-petrographic, diffractometric and electron microscopy investigation of Porta Nuova stones, which brought to a classification of both natural and artificial materials. The results indicate the presence of different ornamental stones, which represent materials recovered from monuments of Roman age.The widespread material is the white Pietra d’Istria in the four varieties Orsera, “vacuolar”, “nodular” and “facies liburnica”. The red “marble” Rosso Ammonitico Veronese is also present to create a beautiful chromatic effect. The valuable architectural components such as the Composite capitals and the columns drums are carved in Marmor Proconnesium and Marmor Troadense, respectively. Peculiar is the use of Pietra di Prun in the capitals’ astragals and of Trachite dei Colli Euganei in the small pillars supporting the upper hinges of the main door. The hanging wall façade is built with recovery bricks of different size and chromatic shades. Characteristic phases (e.g. gehlenite, analcime, cristobalite) detected by diffractometric analysis confirm that bricks derive from high temperature firing of the mixture in furnaces. Bricks surface grinding (“sagramatura”) was a common feature. Original lime bedding mortars and finishing plaster mortars with fine sand framework have been distinguished in the hanging wall. A late microconglomeratic finishing plaster mortar has also been detected, likely ascribed to a restoration intervention after the second World War.

- A new light on Black-Gloss Tiberine manufactures: the Colle Rosetta settlement (Latium, Italy). A preliminary study.

- Within the framework of the studies regarding Black-Gloss Pottery, this paper focuses on the subject of Sabine Tiberine production. Some sherds of Black-Gloss Pottery found in the settlement of Colle Rosetta (Sabina Tiberina - Rieti) in the 1970s were analysed. Chronologically, the period of production of all the fragments found ranges from the latter half of the 4^th century to the first half of the 1^st century B.C. The period spanning from the 4^th to the 3^rd century B.C. appears to be the peak period for the production under study as regards quality of artefacts. The geological investigation and the preliminary diffractometric, petrographic, chemical and SEM analyses carried out on the sherds and on the quarry samples taken from three different accessible clayoutcroppings near the archaeological site highlighted a probable local manufacture of the sherds. This finding is very important because it would be the first evidence of the existence of a ceramic workshop in the Tiberine area. SEM analyses carried out on the Black-Gloss provided some details regarding the grade of vitrification and its composition. In particular, the total iron contents are very similar to those found in the gloss of Northern Etruria, of Ariminum and in Attic Black Figure Vases. So it is possible to imagine an imitation by Italic potters of the technological standardisation in providing this Fe-enrichment to obtain the Black-Gloss used by Greek craftsmen.

- Post-medieval glass from the Castle of Cosenza, Italy: chemical characterization by LA-ICP-MS and SEM-EDS.

- This work reports results of the chemical characterization of twenty-six samples of variously coloured post-medieval glass fragments found during excavations near the Castle of Cosenza (Calabria, Southern Italy). All the glass fragments are currently housed in the City Museum of Cosenza. They were studied by scanning electron microscopy with energy- dispersive X-ray spectroscopy (SEM-EDS) for major elements and Laser Ablation Inductively-Coupled Plasma Mass Spectrometry (LA-ICP-MS) for trace elements and REE concentrations. Information on the provenance of each find and the technology of glass-making was obtained.