This astrolabe, dated AH929 (1522-23 AD), is signed by one Yusuf ibn Hajji al-Jilani, from Gilan, a region southwest of the Caspian Sea. It is in the tradition of those made 150-250 years earlier by four successive generations of the Kirmani family. Hajji al-Jilani is not known to have made any other instruments.

The throne is solid and triangular in shape. Engraved in the mater is a geographical gazetteer with the longitudes, latitudes and qiblas of 31 localities. The rete, with 26 star pointers, is a replacement from either Iran or India, possibly from the 18th century. There are four plates, which, instead of having a square notch at the bottom, are held in the mater by a small hole on the lower part of the meridian line which is fixed onto a knob protruding from the mater. Between them, the plates cover all even latitudes between 30º-40º inclusive and also 22º. On the back of the instrument in the upper-left quadrant is a shadow square, outside of which the maker has put his signature in a clear naskhi script: 'Made by Yusuf ibn Hajji al-Jilani in the year 929 Hijra, 892 Yazdigird'. The original peg and wedge for the alidade have been replaced with a modern nut and bolt.