Supplemental salt, minerals and trace elements compressed and sometimes heat treated in a mould to form a block or brick. Most have very low levels of minerals and may contain as much as 98% salt. Designed principally for cattle and sheep many blocks are very hard and suitable only for ruminants as they have rough tongues covered on top with filiform papillae which can rasp off the surface of the block. Horses have smooth soft tongues and the intake from ruminant blocks may consequently be too low to be useful nutritionally. So called Cold Pressed blocks are softer and more suited to use for horses. Suitably formulated mineral blocks can provide a convenient and viable way to supplement various minerals and trace elements on a self-feed basis.