I am making small plaster molds. I don't plan on painting over the plaster with paint. What would be a good seal to prevent plaster dusting off or dirt getting in the pores? This is for jewelry. Will shellac or mod podge work fine?

I want to make imprints of my niece's hands and then paint them and have them and have them fired at a local "Paint Your Own" craft store.

I called the store, and the woman I spoke to said she fired all of her pieces on 6. I'm not familiar with Pottery Kilns and I don't know what type of clay/plasters, can withstand being fired on 6.

I want this to be a nice looking imprint, not just your regular "Plaster-o-Paris" painted print.

I need to know what type of material to use.

I also welcome any other nifty ideas! Thanks!

What would be an easy/ interesting/ affordable way to display a large, (over 100), collection of hockey-pucks. I'm thinking of a shelf made of of some type of L shaped trim moulding with a grove notched in the inside for the puck to rest and the opposite side attached to wall. I'd like to make it easy for people to pick them up and examine them. The display will be surrounding a game room in basement with plaster over concrete-block walls.
Any ideas?
Thanks!
-pik'