The mystery of Ketetiya's blue pearl (2)

How to overcome documentary and narrative asymmetry ? Contact space and agentivity. The city of Ghâna described by al-Bakrî (11th^century ). A model for thinking about interaction: a magnetic field. Comparative chronology of trans-Saharan and transoceanic interactions : three phases. Islamic dissent and initial contacts. Classificatory designations of Africans (Sûdân, Nûba, Habasha, Zanj). The religion of Ghâna according to al-Bakrî (11th^century ). The religious landscape of the western Sahel in the ^mid-11th century. The flowering of Arab funerary inscriptions in the ^{11th-13thcenturies} : the regions. Two corpora : Dahlak (Eritrea) and Tadmekka-Gao-Bentya (Mali). The rise of new towns in the ^11th-13th centuries. The political and economic apogee of African kingdoms in the ^{14th-15thcenturies} . The frontiers of Africa : Ibn Battûta (14th^century ). The blue pearl : return and end.