The Violet Keystone is the sixth and last book in Garth Nix's The Seventh Tower series, published in 2001 by Scholastic.

[1] The cover design and art are by Joan Moloney and Steve Rawlings respectively.

In this book, they travel one last time to Aenir, release their bonded Spiritshadows, and confront the mighty dragon Sharrakor.

After the novel's initial publication by Scholastic it was reprinted by HarperCollins in 2010[2] and then translated into German in 2002, Portuguese and Czech in 2003, and Swedish in 2005.

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