Neodymium is a rare earth element, that when combined with iron and boron creates a very powerful magnet (NdFeB). The shape of these magnets makes it easy to remove them from boards as the pull is so strong that flat neodymium magnets can be difficult to remove from some surfaces! The shape also allows for string to be attached between them – identifying trends or patterns. These magnets are particularly suitable for use on our glass whiteboards where a stronger magnet is required.