Guilds or Shrines were organizations of trades and artisans. It is the Guilds that collected the raw materials and supplied manufactured goods to the markets. They worked like the modern banks, protecting the interests of their members. They also settled quarrels among members, issued their own coins and gave grants to educational institutions. Some Guilds became so strong that even the kings could not ignore them. To make enough different things for the use of the rich people who lived in the citadels, the artisans used iron tools.