The Zero Stone

From Author Wars - https://authorwars.com/publications/the-zero-stone-260373.html

Overview:

Title: The Zero Stone
Author: Andre Norton
Year: 1969
Publisher: Ace Books
Price: $0.60
Pages: 221
Binding: Paperback
Type: Novel
Title Reference: The Zero Stone
Notes:
No printing or edition stated Date from Stuart Well's ACE Notebooks The artist is not credited, J. Jones is on the artwork Interior art not credited or signed but looks like Jack Gaughan