There is a big display case that holds 10 items and a display case that holds 8 items. Both of the you can activate, but as to whether which one is the best for what gem, metal, etc, I am not sure. I have used them both and find they work about the same. I use the big one most of the time, I finally got a large gem, which I had never gotten before. I am sure someone can go into more detail and has had more exerience in testing these things out than I have. Personally, I believe you can put the same combination on them both.