Exposed aggregate is not a new concept. It has been in existence for over a hundred years now. This technique is believed to have started the decorative concrete trend. The name says it all. Exposed aggregate is a type of concrete in which the top layer is removed. It does not affect the functionality of the concrete surface; rather, it is intentionally done to expose the aggregate underneath.
Aggregates can include a wide variety of objects, including gravel, sand, glass, and quartzite. The finished result can be compared to a more flexible version of marble or granite.