Iron mine!
This is the real strategic resource of Mianshui County, the foundation of their wealth.
Trafficking in illicit salt may be forgivable, but illicit iron mining is a genuine capital offense.
But there are exceptions, such as guilds recognized by the court, which have the qualifications to mine iron ore.
For example, the two dominants of Mianshui County: the Fishing Guild and Guild Cao!
They are permitted by the court to mine for iron ore, which is a reflection of their extraordinary status. Of course, even though they are allowed to mine, there is still some control.
Each month they must submit a fixed proportion to the court; only the remaining can they sell privately.
Of course, this private selling also depends on the buyer; they can only sell to blacksmiths forging agricultural tools, and some can be used within the guild, but it is all controlled.
