“The Moonstone Castle Mystery” by Carolyn Keene

I always enjoy a mystery that finds our female-sleuth exploring an old mansion or castle. So many secrets must be hidden in those walls!

This is book 40 in the Nancy Drew series, published in 1963. According to Wikipedia, the actual author of the book was ghostwriter Harriet Stratemeyer Adams.

There are two mysteries in this book. One involves a case that Nancy’s father, attorney Carson Drew is working on. Mr. Drew is asked to find a young woman named Joanie Horton because she is due an inheritance. Nancy and her friends are asked to help and so the case leads them to a town called Deep River.

The second mystery involves a moonstone that Nancy receives anonymously. While in Deep River, Nancy and her friends discover a castle named Moonstone Castle which comes complete with a drawbridge and moat.

As her investigation continues, Nancy begins to realize there is a connection between the two cases.

While reading this book, I wondered what a moonstone looks like so I found a few pictures:




Basically moonstones are classified as mineral gemstones of the feldspar variety. The stone has a milky, bluish color caused by the refraction of light from its thin, paired internal layers.

You can read more about moonstones at the
GemSociety.org.