1000 Rials - Mohammad Rezā Pahlavī 7th. portrait, 'Dark Panel'

By the late 1960s, Bank Markazi Iran had consolidated around Harrison & Sons for much of its high-denomination printing work — the relationship produced several overlapping portrait series, which is precisely why collectors distinguish this issue as the "Dark Panel" type. The term refers to a deliberate design modification made mid-series to improve visual separation between the central vignette and surrounding fieldwork, a change Harrison implemented at the bank's request rather than as a routine reprint variation.

At the 1000 Rial level, these saw genuine heavy circulation — Iran's oil revenues were driving rapid economic expansion, and large-denomination notes moved through commercial channels constantly. Worn examples are the norm.