Where was lustre glazing first developed in the Muslim world?

The development of lustre glazing in the Muslim world is a subject of scholarly discussion, with evidence pointing primarily to two regions:

• Iraq: Many scholars believe that the technique of lustre glazing was first developed in Iraq. During the 'Abbāsid period, ceramicists in this region sought to imitate imported Chinese ceramics, leading to significant technical innovations.12
• Egypt: Some researchers argue that the technique originated in Egypt rather than Iraq. This perspective is supported by the existence of the earliest datable lustre object—a glass goblet inscribed with the name of a governor who ruled in 773 CE, which is currently held in the Cairo Museum of Islamic Ceramics.1

While the exact origin remains a matter of academic debate, it is widely accepted that Islamic potters perfected the technique to provide clay objects with a metallic, shiny appearance, often to simulate vessels made of precious metals.21