This article discusses a hitherto unknown unsigned early European astrolabe kept at the Liceo Classico Alighieri in Ravenna. The astrolabe was made in Toulouse in 1216 and later seems to have been moved to Ravenna. Our investigations of the lettering, the design features, and the stars on the rete of the astrolabe show that the instrument was modelled on an Andalusian model dating to the last quarter of the 11th century.
Arnaldi et al. (Fri,) studied this question.