This corner shelf is made out of Recycled Glass engineered stone. It was made in our fabrication shop, has a polished eased edge and is 3cm thick. The measurements (7",8",9",10" or 12") are from the front of the shelf to the point on the back.
These shelves are made out of real counter top slab material not from tile. The shelves are to be set with tile mortar on top of a row of tile and the next row of tile cut around the shelf locking it in. If you are wanting to set this shelf on the surface of an existing shower look at the installation of 3cm shelf instructions tab at the top of the page.
The under polish option is there if you would like to have the polished look on the bottom of the shelf. For example, your shelf is above eye level and you would prefer it look the same as the shelf beneath it.