Buwayhid, Sultan al-dawla (403-415h), Dirham, Shiraz 406h, obv. central legend arranged in and around enlarged lam-alifs, 3.42g (Treadwell Sh406; A 1581). Very fine, rare.
The second line of the reverse legend reads malik al-muluk shahanshah; this appears to be the reading on the coin illustrated by Treadwell, although his transcription of this line is different.
Estimate: £120-150