Stall inventory

Ok so I have a question about stalls.
So you have 6 slots to sell items from. now say you used the first slot for leather.
does all of the items in that slot require same purity and chemical make-up?

would you be able to put all of these on the same slot at the same time?
So you have 6 slots to sell items from. now say you used the first slot for leather.
does all of the items in that slot require same purity and chemical make-up?

would you be able to put all of these on the same slot at the same time?