The Black Stone

From Author Wars - https://authorwars.com/publications/the-black-stone-275656.html

Overview:

Title: The Black Stone
Author: Katharine Kerr
Year: Unpublished
ISBN-10: 000712869X
Publisher: Voyager
Pages: 368
Binding: Hardcover
Type: Novel
Title Reference: The Black Stone
Notes: Nov-2008 Uploaded from Amazon.co.uk. Despite a reader review this is a vaporware title as no copies are available for sale via AbeBooks. BookFinder does not have any copies available either and also reports this as The Spirit Stone by Katharine Kerr and published by Zondervan. The author reports "A number of people now have sent me email about a Deverry book they've seen advertised as The Black Stone. This book does not exist. The title you're looking for is The Spirit Stone."