100 Francs Petra

Niger has issued a long-running series of miniature gold coins under the "Petra" name, each tied to a UNESCO World Heritage Site. The Jordanian city of Petra — carved by the Nabataean Arabs into rose-red sandstone cliffs and flourishing as a trading hub from roughly the 4th century BC — was largely unknown to the Western world until Johann Ludwig Burckhardt located it in 1812 by disguising himself as a Muslim pilgrim.

KM#44 is among the smallest gold coins in active catalog circulation, a format Niger's treasury has used to attract the bullion novelty market rather than domestic commerce.