Sumerian temple hymn to Iddin-Dagan

Here we see, apparently, a cuneiform hymn to Iddin-Dagan, lugal of Larsa, from the 19th century BC, inscribed on a hexagonal artifact of some sort. It is my understanding that the Sumerians of yore made similar inscriptions on otherly-shaped blocks as well—square, pentagonal, etc.—but I would like to think there was some religious significance to the choice of a hexagon here.