The bricks were new left over from about 40 years ago. They were new brick supposed to represent used brick. They had what looked like different color paint slopped randomly over them. It was a style back in the 70's. One of my relatives used to call them hen house bricks, he said they looked like they had been lying around in a chicken coop. I didn't like the hen house look so I laid them backwards, face side in. They are hollow, except for the ones around perimeter of the hearth. I found enough solid ones for that. Firebrick inside and around firebox. I assume the holes in the red brick had something to do with the manufacturing process. The best part about the bricks was the price, free.
I concreted in a 6x6 post for the post vise this evening. Restoring the antique bellows and post drill are next.