20 Riels - Norodom Sihanouk (Monoclonius)

The 1995 20 Riels coin featuring the Monoclonius is part of a broader series of commemorative coins issued by the Kingdom of Cambodia during the mid-1990s. These coins were produced to celebrate the country's rich natural history and biodiversity, specifically focusing on prehistoric themes that gained popularity in numismatic circles during that decade. The series was designed to appeal to both domestic collectors and the international market, showcasing a blend of Cambodia's regal heritage under King Norodom Sihanouk and global scientific interest in paleontology.

The design highlights the Monoclonius, a genus of herbivorous ceratopsian dinosaur, intricately rendered on the reverse side. The obverse features the official state emblem of Cambodia, reflecting the era's focus on national identity and restoration following the transition to a constitutional monarchy. These coins were struck with a high level of detail, characteristic of commemorative issues minted to serve as both legal tender and collectible artifacts for the growing numismatic community in Southeast Asia.