The Adventures of Joe-Joe Nut & Biscuit Bill: Case #2: Mineral Mischief is the second book in a series of detective books written for elementary students. It is 74 pages long and has black and white illustrations throughout. It is divided into seven chapters, and it concludes with a few pages of factual information and experiments.

In this book, Joe-Joe Nut and Biscuit Bill are called on to help find Maple Moo's missing mineral. The story opens with Joe-Joe Nut cornered by gang of teenage bully lions (whose plans are foiled when their father shows up), and it then moves into the case of the missing mineral. The two detectives interview various residents of Acorn Valley, eventually solving the case. This fun detective story is filled with information about geology, including facts about volcanic rock, gemstones, quartz, and others. So while Joe-Joe Nut and Biscuit Bill solve the crime, the reader learns all about rocks and minerals.

The book ends with an experiment called "Bubbling Rocks." There is a supply list, and the supplies are basic household items or are easily obtained if you don't have them on hand, with one exception--limestone is suggested, though you can substitute chalk. The experiment simulates acid rain and is easy to perform.

Overall, I think The Adventures of Joe-Joe Nut & Biscuit Bill: Case #2: Mineral Mischief is a fun book and would be a good basic geology introduction or an entertaining supplement to a science curriculum. It's also an entertaining read for young rock hounds.