with optional cow. This is the cut stone that is commonly used in Nic. blocks are about 5 x 15 x 24 inches. This wall is defintely overkill for any use-value, but some people seem to like the stuff. Often it is just used for the below grade portion of a wall or building because it is more water resistant than brick.
Structurally it scares me, but I recently talked to someone building a house south of Managua who told me his contractor drills holes in it to insert rebar. Seems like a good idea for tall applications, but I´ve haven´t happened to see that done around here. Usually it´s just put up between the usual concrete and iron structural members.
I just did a patio floor with it. Its cheaper than concrete and stronger than brick, and not bad looking.
Note: sloppy mortar work is a northern tradition. If you want it done pretty, you have to specify in advance and supervise the work carefully.