Not sure that black markets qualify as a free market. They are created usually due to centralized forces targeting the goods with violence, which creates an artificial value on the goods as customers pay premiums to circumvent the central thugs. I often think much of what is illegal is made so to create these markets so the central powers can themselves profit immensely as they can move in and out of them at will without worry of being caught up in their own punishment systems.

Not familiar with african "system d" what is it?