Best known as the home of The Overstreet Comic Book Price Guide, Gemstone Publishing was formed by Diamond Comic Distributors President and Chief Executive Officer Stephen A. Geppi as a conduit for his efforts in preserving and promoting the history of the comics medium.
In the early 1990s, Gemstone separately acquired Russ Cochran Publisher and Overstreet Publications, which brought with them The Complete EC Library and the noted line of price guides, respectively. As a result, Gemstone also publishes The Overstreet Comic Book Grading Guide, The Big Big Overstreet Comic Book Price Guide, Hake's Price Guide to Character Toys, and The Overstreet Toy Ring Price Guide, and co-published Tales of Terror! - The EC Companion with Fantagraphics Books. Gemstone has also published to date 13 hardcover volumes in the EC Archives series, reprinting the original EC Comics from the 1950s in chronological sequence in a high-quality format.
From 2003 through 2008, Gemstone, in collaboration with Disney Publishing Worldwide, published Disney Comic Books featuring many of the beloved characters that had not appeared on comics shop shelves for years, including Mickey Mouse, Minnie Mouse, Donald Duck, Goofy, and others.
In 2002, Gemstone added Scoop, a free, weekly information e-mail newsletter, to its list of popular publications.