Naslov
Roman pottery workshops in the province Dalmatia: identifying clay sources and production technology through mineralogical analysis

Autori
Grizelj, Anita ; Konestra, Ana

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
9th Mid-European Clay Conference, Conference book / Tibljaš, Darko ; Horvat, Marija ; Tomašić, Nenad ; Mileusnić, Marta ; Grizelj, Anita - Zagreb : Hrvatsko geološko društvo, 2018, 50-50

ISBN
978-953-6907-71-7

Skup
9th Mid-European Clay Conference (MECC 2018)

Mjesto i datum
Zagreb, Hrvatska, 17.09.2018. - 21.09.2018

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
clay minerals ; Roman pottery ; X-ray diffraction ; firing temperatures

Sažetak
Several pottery workshops and seemingly isolated kilns dated to Roman times have recently been identified in the coastal area of province Dalmatia (eastern Adriatic), more precisely in its northernmost part, ancient Liburnia. Within a programme of archaeometric analysis1, mineralogical characterisation of clays and pottery samples was carried out in the attempt to identify clay sources utilised for pottery production and determine the temperatures of firing. For this purpose, samples of production waste from four kiln sites (Crikvenica, Plemići bay near Ražanac, Podšilo and Mahućina bays on Rab Island) were compared to potential clays sourced in the vicinity of the sites. Mineralogical analysis of clayey materials included X-ray powder diffraction (XRPD) on pottery samples and clayey materials. Clayey materials were also analysed on random mounts of bulk samples and oriented mounts of the <2µm fraction. Oriented mounts of the <2 µm fraction were recorded after the following treatments: a) air drying, b) saturation with K+ and Mg2+, c) ethylene-glycol solvation, d) heating to 400°C and 550°C. The determination of the pottery firing temperature included drying modelled clayey materials at room temperature for 4 days and firing at temperatures ranging from 700 to 850°C. The mineralogical analyses showed that the main mineral components of all clayey materials are quartz, swelling clays and illite/muscovite. Calcite is present in samples from Crikvenica and Plemići. Among the swelling clays smectite is dominant in samples from Crikvenica, Plemići and Podšilo, while vermiculite is dominant in samples from Mahućina. Feldspar and kaolinite are present in a lesser quantity in all samples, while chlorite is present only in some samples. Quartz is the main mineral which is regularly present in all pottery samples. Pottery samples together with quartz also contain some of these minerals: illite/muscovite, calcite, feldspar, hematite and clinopyroxene. Results point out that in some cases the clays collected from sources identified in the sites environs could have been utilised in pottery production and the mineralogical composition of clays and pottery sherds helped identifying the possible firing temperatures. Thus, results offer a valuable insight into facilities' installation choices, production organisation and technology. Acknowledgments: 1This contribution and the analysis carried out are activities of Project RED - Roman Economy in Dalmatia: production, distribution and demand in the light of pottery workshops (HRZZ, IP-11-2013-3973).

Izvorni jezik
Engleski

Znanstvena područja
Geologija, Arheologija

POVEZANOST RADA