After a lot of research on store names, I decided to use regional parks for my inspiration. They're linked to the community and they often have colorful names. For example, I considered Wildcat Games, named after the Wildcat Canyon Regional Park near my house. I still think that area could use a game store. Think of a regional park in your area and see if I'm right.
Black Diamond Games was named after the Black Diamond Mines Regional Park in Contra Costa County. "Black Diamond" refers to the coal that was mined from this region in the 1860's. Most people in the area know nothing about the park. A number of people accused me of ripping off "Black Diamond" from other local businesses. I did a business search and there were over a hundred "Black Diamond" businesses in California. If I'm guilty of anything, it's lack of originality.
One of my customers who knows the history of the park very well runs an interesting Dungeons & Dragons adventure at the local convention (Dundracon). He uses actual maps of the Black Diamond mines for a dragon's lair.
Our logo has a story too. We took the name Black Diamond Games and sponsored a logo design contest. We gave some vague logo design guidelines and let graphic designers from all over the world compete. There were wizards that looked like the Dungeon Master from the D&D cartoons (some looked like child molesters). There were simple diamond shaped designs. There were scary knights that were likely to give small children nightmares. I wish we had kept all the logos that didn't make it. Some were really interesting. Below is the winner, by a designer known as "Blazen." My total cost for the logo was about $250.
There's an alternate design floating around my hard drive where the knight is wielding a sword, but for some reason it seems violent, as if wielding a lance can be related to a game, like jousting, while a sword shows more lethal intent. Every once in a while that sword wielding knight accidentally ends up on a document by mistake.