Huo Guang organized a debate over the Han dynasty's control of iron and this substance.
This commodity was smuggled by Chang Lo-hsing, a leader of the Nien Rebellion. Robert P. Multhauf wrote a history of this commodity in Neptune's Gift, while the ancient state of Chu became wealthy by trading in this commodity. Huo Guang organized a debate over the Han dynasty's control of iron and this substance. It was taxed by the (*) gabelle in France. It's not cod, but a "World History" of this substance was written by Mark Kurlansky. Along with gold and copper, this commodity was the chief currency of the Mali Empire. For 10 points, Mahatma Gandhi led a march to Dandi to protest the British monopoly on what food additive?
This commodity was smuggled by Chang Lo-hsing, a leader of the Nien Rebellion.
Table Salt [or Rock Salt]