Dells Mining Co is a nice little shop for stones, gems, and jewelry. Some raw minerals, many polished stones. Also a "panning for gold" type of activity for young and old. They also have helpful staff able to explain the various types of minerals. All in all a pleasant side trip on the main drag of the Wisconsin Dells.
Fun for the kids. They sell a variety of things: jewelry, magnets, nightlights, etc. utilizing different stones and precious stones. You can also pan for your own precious stones. They have multiple buckets for different prices so you can pan for them yourself.