Fig 1.
Unguja Ukuu site plan showing locations of excavated trenched.
Most of the glass vessels came from Trenches UU10, UU11, UU13, UU14 and UU15.
Table 1.
Description of the glass vessels from Unguja Ukuu.
Fig 2.
Examples of glass vessels from Unguja Ukuu.
(A) Closed flaring–wide mouth GL2475; (B) Closed flaring–wide mouth GL3255; (C) Ribbed (narrow) GL1637; (D) Ribbed (narrow) GL1638; (E) Stepped rim GL1029; (F) Stepped rim GL0040; (G) Plate (tooled) GL2147); (H) Miniature jar GL1343; (I) Scratch-engraved GL0090; (J) Scratch-engraved GL2244; (K) Vertical neck–wide GL0143.
Table 2.
The means and standard deviations of Unguja Ukuu glass vessels.
Fig 3.
A biplot of TiO2/Al2O3 vs. Al2O3/SiO2 for Unguja Ukuu natron glass vessels with relevant 4th– 9th centuries AD natron glass groups found in Egypt, Israel and Tunisia.
The data is displayed according to compositional groups and sites. Data are from: Egypt 1a, 1b, 1c, Egypt 2 high Na2O and low Na2O [13]; Levantine I and Foy 2.1 glass from Khirbat al-Minya [38]; Levantine II glass from Ramla [10]; HIMT 1 and HIMT 2 glasses from Carthage [39].
Fig 4.
A biplot of Ce/Zr vs. Y/Zr for Unguja Ukuu natron glass vessels with relevant 4th– 9th centuries AD natron glass groups found in Egypt and Syro-Palestine.
The data is displayed according to compositional groups and sites. Data are from: Egypt 1a, 1b, 1c, Egypt 2 high Na2O and low Na2O [13]; Levantine I and Foy 2.1 glass from Khirbat al-Minya [38]; Levantine II glass from Ramla [10].
Fig 5.
A biplot of Zr vs. Ti for Unguja Ukuu natron glass vessels with relevant 4th– 9th centuries AD natron glass groups found in Egypt and Israel.
The data is displayed according to compositional groups and sites. Data are from: Egypt 1a, 1b, 1c, Egypt 2 high Na2O and low Na2O [13]; Levantine I and Foy 2.1 glass from Khirbat al-Minya [38]; Levantine II glass from Ramla [10].
Fig 6.
A biplot of Th vs. La for Unguja Ukuu natron glass vessels with relevant 4th– 9th centuries AD natron glass groups found in Egypt and Israel.
The data is displayed according to compositional groups and sites. Data are from: Egypt 1a, 1b, 1c, Egypt 2 high Na2O and low Na2O [13]; Levantine I and Foy 2.1 glass from Khirbat al-Minya [38]; Levantine II glass from Ramla [10].
Fig 7.
A biplot of Al2O3 vs. MgO/CaO for Unguja Ukuu plant ash glass vessels with relevant 4th– 9th centuries AD plant ash glass groups found in Israel, Syria, Iraq and Iran.
The data is displayed according to compositional groups and sites. Data are from: Samarra Groups 1 and 2 and Cobalt Blue flasks [12]; Ctesiphon, al-Raqqa, Nishapur and Khirbat al-Minya [7]; Siraf Low Zr glass [42]; al-Qadisiyya [43].
Fig 8.
A biplot of Cs/K vs. Li/K for Unguja Ukuu plant ash glass vessels with relevant 4th– 9th centuries AD plant ash glass groups found in Israel, Syria, Iraq and Iran.
The data is displayed according to compositional groups and sites. Data are from: Samarra Groups 1 and 2 and Cobalt Blue flasks [12]; Ctesiphon, al-Raqqa, Nishapur and Khirbat al-Minya [7]; Siraf Low Zr glass [42]; al-Qadisiyya [43].
Fig 9.
Biplot of 1000Zr/Ti vs. Cr/La for Unguja Ukuu plant ash glass vessels with relevant 4th– 9th centuries AD plant ash glass groups found in Israel, Syria, Iraq and Iran.
A The data is displayed according to compositional groups and sites. Data are from: Samarra Groups 1 and 2 and Cobalt Blue flasks [12]; Ctesiphon, al-Raqqa, Nishapur and Khirbat al-Minya [7]; Siraf Low Zr glass [42]; al-Qadisiyya [43].