We use the description "Magnetized thruthickness" to identify the locations of the poles on our block magnets. The thickness is always thelast dimension listed for block magnets.
If you take one of our block magnets and place it on a flat surface with the thickness dimension as the vertical dimension, the poles will be on the top and bottom of the magnet as it sits.
If you place one of the blocks so it is on a flat surface with 1/8" as the vertical dimension, the poles will be on the top and bottom as the magnetises.
This means the poles are located in the middle of the 1" x 1/2" sides.