Soil Trading, also known as Dirt Trading was the act of trading soil or dirt, which had become a vital and expensive commodity in the years following the 'Great Rise' before colonisation. Many dirt traders were members of the Persephone Traders Guild, the Dirt Traders Guild, was a smaller guild within the PTG, that directly dealt with dirt trading. Dirt Trading was not deemed illegal by the government, as they saw soil as a necessary commodity, although dirt traders had to be licensed to trade in the larger cities, where the governments administration is more prominent.