Preparing a new workshop

I've been asked to give a workshop 'mold making' many times and I've always been hesistant for a few reasons. One of them is that it's a very, very messy activity. I just couldn't imagine having more then 1 person in my studio making a mess but well, I've given in and the first workshop will take place at the end of april. I'll be sure to make a picture before and after. :)

So right now, I'm doing some preparation work and I'm making a few molds for people to use in the workshop. One of my co-workers bought an old house a while ago and she mentioned that she found so many old keys. Haha, that sounded like music to my ears so I asked her if I could mold them.
They have been laying about in my studio for quite some time but now I finally find the time to make it happen.

I made a double mold for pooring clay slib into it. It's drying now so I'll post a picture when I finish a porcelain key. Here are some images of the process: