10 000 Francs CFA Van Gogh, Portrait of Dr. Gachet

Chad's CFA franc is issued under the authority of the BEAC — the Central Bank of Central African States — which means any commemorative struck in Chad's name is, in monetary terms, a fiction of sovereignty. These large-format novelty pieces are produced entirely for the collector market by European minting houses, with no meaningful connection to Chadian monetary policy or circulation. The Portrait of Dr. Gachet has its own complicated history: painted in 1890 just weeks before Van Gogh's death, the original sold at Christie's in 1990 for $82.5 million — then the highest auction price ever paid for a painting — and has not been publicly exhibited since.