What is the ingredients in a salt lick, as in a salt lick for your horses? Need to know the chemical make up?

I need to know what kind of salt and any other ingredients that I can find out that are in a salt lickWhat is the ingredients in a salt lick, as in a salt lick for your horses? Need to know the chemical make up?
The principal ingredient is Sodium chloride otherwise known as table salt.





Depending upon the supplier it may also contain Sodium or Potassium iodide and or Potassium chloride.What is the ingredients in a salt lick, as in a salt lick for your horses? Need to know the chemical make up?
A salt lick is a natural formation of salt. Salt is a mined product, and this is a deposit that reaches the surface.





A salt *block* is manufactured.





You can buy salt blocks that are just salt; they tend to be white. You can also buy salt blocks that contain other minerals, which tend to be brown or gray.





The added minerals will vary by manufacturer, and according to the livestock it is intended for.
i don't know what salt it is