Substantial development in the pearling industry around the Qatari Peninsula occurred during the Abbasid era. Ships voyaging from Basra to India and China would make stops in Qatar's ports during this period. Chinese porcelain, West African coins and artefacts from Thailand have been discovered in Qatar. Archaeological remains from the 9th century suggest that Qatar's inhabitants used greater wealth to construct higher quality homes and public buildings. Over 100 stone-built houses, two mosques, and an Abbasid fort were constructed in Murwab during this period. When the caliphate's prosperity declined in Iraq, so too did it in Qatar.