Final answer:
Obsidian, a type of volcanic glass formed from lava cooling rapidly with no time to form crystals, is likely what was found at Ali Kosh. Islamic luxury glass, known for its high quality, was exported to Europe and China, reflecting the advancements made by Muslim craftsmen. The Serçe Limanı shipwreck findings support the historical significance of the glass industry in that region.
Step-by-step explanation:
The type of volcanic glass found at Ali Kosh in eastern Turkey is likely obsidian, a naturally occurring glass formed from volcanic activity. Obsidian is created when lava cools rapidly with minimal crystal growth, usually having a composition of rhyolite. This material, known for its smooth fracture patterns, was commonly used in the past for tools and decorative items. Islamic glass was highly sophisticated throughout the Middle Ages, reflecting the significant advancements in glassmaking within the Islamic world, which had inherited much of the traditional glass-producing regions from the Sassanian Empire and the Ancient Romans. Historically, Islamic luxury glass was of exceptional quality and widely exported. In the 8th century, the first industrial complex for glass and pottery production was established in Ar-Raqqah, Syria. Between the 8th to early 11th centuries, luxury glasswork focused on surface manipulation techniques to achieve decorative effects, culminating in the production of items like the Hedwig glasses. Other information related to glassware includes the findings from the Serçe Limanı shipwreck off the coast of Turkey, which dates back to the eleventh century. The shipwreck yielded glassware, cullet (glass waste), and Islamic ceramic vessels. These findings underline the historical importance of the glass industry which saw a shift to Egypt and Syria from the 12th century onwards as the major production centers for luxury glass.