Much of Morocco’s Anti-Atlas Mountains are built of Paleozoic rocks, dating back to between 245 and 570 million years. When these rocks were deposited, a shallow sea covered the region. Trilobites scuttled along the seafloor, and huge schools of Orthoceras, squid-like nautiloids with cone-shaped shells, swam above. When they died, their shells were preserved in the limy mud of the Maidir basin located between Erfoud and Alnif, awaiting resurrection as the polished curios, coffee tables and ornamental sinks that now cram Alnif’s roadside shops.
Today more than 50,000 Moroccans earn their livelihoods in the fossil and mineral specimen mining and export business. It's hard, labour-intensive work where men work the fossil-rich seams and old mining spoil heaps by with chisels, picks and hoes. Prices depend on rarity, condition and the quality of the workmanship in the preparation, and can range from tens of dirhams to tens of thousands of dirhams for museum-quality specimens.