Question

Could you use a bluestone as bondstone in a brownstone wall?

Answer

You could, but you probably wouldn’t want to. Brownstone is sandstone often used in walls. A bondstone is a stone used to anchor or bond a stone veneer to its backing material. Bluestone is dense, hard feldspatic sandstone that readily splits along it bedding planes to form thin slabs. It is most typically used for flagging (flagstone floor finish).