When you visit Fez, you should try to visit the leather tanneries there. Leather is a big industry in Morocco and when you visit a leather tannery, you realize what is actually involved in the leather tanning process and it is quite remarkable. You don't realize how poor the conditions are for the workers there, you cannot smell it through my photos, but it will definitely hit you once you get there.
If I remember correctly, there are two types of vats. One for helping to remove the fur from the skin and one for dyeing the leather after. Each of the vats hold a different colour dye for colouring the leather and you will see at the top how they hang the skin to dry.
Unfortunately, I did not keep many details when I was on this trip, so I don't recall which leather tannery we visited, but it seems like you cannot go wrong with going to any of the big three leather tanneries in Fez.
Come back next Friday for another Past Point of Interest!