There is a fine terracotta inscription in elegant thuluth characters at the top of the minaret. This is taken from the openeing verses of the 20th sura of the Quran, Ta-Ha, and presumably relates to the axial symbolism of the minaret as a link between Heaven and Earth, between God and Man.
The inscription reads as follows:

which translated means:
In the name of God, the Compassionate, the Merciful. Ta Ha.
We have not sent down the Qur'an to thee to be (an occasion) for thy distress,
But only as an admonition to those who fear (Allah),
A revelation from Him Who created the earth and the heavens on high.
(Allah) Most Gracious is firmly established on the throne (of authority).