An Islamic Brass Astrolabe with Openwork Rete and Multiple...

An Islamic Brass Astrolabe with Openwork Rete and Multiple Latitude Plates.
A finely engraved Islamic brass astrolabe composed of multiple interchangeable plates (tympans), a rete with intricate cutouts representing fixed stars, and a rotating alidade. The piece is densely inscribed with Arabic numerals, star names, calendrical notations, and Islamic astronomical markers in elegant naskh script.
The throne is surmounted by a ring for suspension and engraved with Arabic calligraphy, including the maker's inscription, which reads:
“O Opener of the doors, open for us goodness.”
The back plate (al-ʿadhud) is filled with concentric scales used for various astronomical calculations, including degrees, zodiac signs, and a calendar with the months inscribed in Arabic.
One plate is marked with the city name Isfahan, indicating it may have been calibrated for use in that region.
H: Approximately 22.5cm
Provenance: Private property of a distinguished NW London collector.