Aesculus seeds were traditionally eaten, after leaching, by the Jōmon people of Japan over about four millennia, until 300 AD.
A few years earlier, Henri Étienne Sainte-Claire Deville in France developed a method for making alumina by heating bauxite in sodium carbonate, Na2CO3, at 1200°C, leaching the sodium aluminate formed with water, then precipitating aluminium hydroxide by carbon dioxide, CO2, which was then filtered and dried.
The toxin can however be removed by careful leaching, and the roots and half-buried stems of this cycad were used by Native American people (notably the Tequesta and Mayaimi Indians, the Seminole Indians and the Maroons) to produce this starch.
In 2004 Barrick Gold is undertaking gold mining 43 km west at Lake Cowal through the process of in situ cyanide leaching, a variant of the controversial process of Gold cyanidation.