That looks like a Sedum (Crassulaceae) to me. (Too bad one can't use italics or underline here, it feels terrible to leave those Latin names in plain format. Also, remember that 'species' is the same word for singular and plural). Could you post another picture if you find it in flower? Flowers will be very helpful to determine the species.
I agree it should be some member of Crassulaceae. However, for me it does not like Sedum, Sempervivum, or Jovibarba (= Sempervivum globiferum group). Most likely it is a member of the genus Rosularia. Please compare the following photo: http://photos.v-d-brink.eu/Flora-and-Fauna/Asia/Iran-Central-Western/i-LfKJfs4 . Unfortunately I do not have good floristic literature on Crassulaceae of Iran.