OMAN. Oman Currency Board. 10 Rials Omani, ND (1973). P-12cts. Color Trial Specimen. PMG Choice Uncirculated 63. A beautiful uncirculated example of this Color Trial Specimen (Blue-Green). Omani coat of arms at right on face, vignette of the Al-Mirani Fort overlooking the harbor and city of Old Muscat on back. PMG Comments "Previously Mounted."