You can get 50 # bags of trace minerals, salts, calcium , etc... at Feed stores, much cheaper than what you'd pay for specialty blends for deer at hunting stores. On a private farm my friend and I hunt, there is a mineral lick that he's develped this way for the past 10 yrs or so. You could park 3-4 cars in it, and its' about 2 feet deep!!!! It can be seen via Google Earth!! sorry , cant disclose the location though, if I remember to take my camera next time we go out---I'll get a pic or it!