I tried some of the brown mineral blocks, but they don't seem to hold up very well and break up quickly if wet, rain or high humidity. I have been using the yellow sulfur mineral blocks for years and put away from my feeders. In a cow rich environment, they will last a month or so but without cows, they can go 3-4 months. These also help keep the ticks down on the deer & hogs if they use them. about 10 years ago, a friend that owns a feed store said he had a new product that was supposed to be a huge attractant for deer, called Trophy Rock. I was pretty skeptical since it was pretty expensive relatively speaking but I bought a chunk, took a hammer & chisel to it to break it down into baseball size pieces to put at multiple different locations as a test. All of the "sand/dust" that remained on my tailgate, I slung out in an area that had a pretty good stand of grass about a foot high. The next weekend, there was a bald spot where the grass was and the baseball sized chunks were the size of golf balls and licked smooth almost to a polished state. Since then, I usually buy one of the big chunks and break it down to put out around my feeders. seems like the deer really like that stuff.
"everyone that lives dies but not everyone who dies lived..."