Ten years ago, I found a crystal deodorant in my bathroom cabinet after my wife and I got married. At first, I just dismissed it as one of her BS new-age ideas. For fun, I started using it. Amazingly, it worked better than the traditional deodorant I was using. Ten years later, I am not going back. I am very active, live outdoors (in my camper) practically year-round with limited access to a shower, and yet I don't have body odour and my clothes do not reek even after a day of hiking, because if I did, my Japanese wife's traditional horror of smell and bacteria would kick in. They do work if you use them as you described, and last at least 18 to 24 months, if not longer.