'Adl / La ilah illa / Allah wahdahu / la sharik lahu ("Just, There is no God but Allah alone, no partner to him”) // Muhammad / rasūl Allāh / Yamin al-Dawla / Mahmud ("Muhammad is the messenger of God, Right Hand of the State, Mahmud”). 10mm, 0.48 grams. Uncertain mint (Ghazni?). Fishman/Todd "The Silver Damma" #GH5 var.

This variety with the additional word "'Adl" ("Just" or "Fair") on top of the obverse, is not listed in Fishman/Todd or other references.

This is a Ghazna type, issued directly under the Ghaznavid Sultan. 

Mahmud of Ghazni (r. 998–1030 CE) was the most celebrated ruler of the Ghaznavid Empire, transforming it into a major power stretching from Iran and Central Asia to northwestern India. Renowned as both a military commander and patron of learning, he launched numerous campaigns into the Indian subcontinent, greatly expanding his empire and accumulating immense wealth. His court at Ghazni became a flourishing center of Persian culture, attracting scholars such as Ferdowsi and Al-Biruni. Mahmud is remembered as one of the most influential Islamic rulers of the early medieval period and for establishing Ghazni as a leading political and cultural capital.