These were not isolated communities exchanging goods with immediate neighbors.

They were embedded in exchange systems that connected people across vast geographic distances.

Whether cave gypsum or mirabilite was a trade good that moved through these networks is not established.

No cache of Mammoth Cave minerals has been definitively identified at a distant archaeological site.

But the existence of these exchange networks means that the possibility cannot be dismissed — and the quantities of mineral that the mining operation appears to have produced were far greater than any single community’s medicinal or ceremonial needs could have required.

The Human Experience Of Total Underground Darkness