Adelaide,There are two sites in the Franklin area that are really good. There is the Franklin Museum in Franklin together with the Buckwheat Mine Dump. And then, three miles away, in Ogdensburg there is the Sterling Hill Mining Museum.
You can collect at both sites. They have poundage fees.
The Franklin Museum is arguably the best display of Franklin minerals anywhere (http://www.franklinmineralmuseum.com/ ). The Sterling Hill Mining Museum (http://sterlinghillminingmuseum.org/) features a mine with all the trimmings, plus a great museum and perhaps the world's best exhibit of fluorescent minerals. It is a guided tour (I suggest you call ahead).
YOu might be able to do Franklin in a long morning and Sterling Hill in a long afternoon, but two days would be better. If I could do only one, I would choose Sterling Hill.
Have a good one!
Don