Something that needs to be remembered is cattle need salt,the problem with salt mixed with minerals is that cattle will only consume the minerals they need and back off. The problem comes when the cattle have tanked up on minerals they may not come back to the feeder thus not getting salt,so if you throw out a few plain salt blocks the cattle still have a option to get salt. You can't expect cattle to eat the "desired" amount some that are lower on minerals will hammer on the tubs till there body says stop,some cattle who's body is okay on minerals will take a mouthful here and there......plus mixed minerals are not cheap so if you got a area of your pasture you want the cattle in but they don't frequent put your white blocks there it will be a better use of your grass grazing between the minerals salt an water......