Be careful with the grams, the 60 grams for €5.80 is very expensive, I fell for it. As a product, it is very good.

I have been using it for 6 years, I believe it is if not the best, one of the best natural deodorants. Just be careful with the stick, because when it falls down, it can break into smaller pieces.
I found this on the internet regarding the potassium alum contained in the crystal:
https://www.sensities.com/protes-yles/protes-yles-kallyntikon/prostheta-kallyntikon/4179/potassium-alum-styptiria

Excellent crystal, On a clean and wet armpit, apply 10-15 times and protects from odor all day even in hot weather. Without clogging the pores, without carcinogenic chemicals. Lasts for many months, which makes it incredibly economical and environmentally friendly.

Excellent and natural product. No comparison to other chemical deodorants. It has no scent. It lasts very long

I didn't see the best results.... I bought it based on the comments but I am not particularly satisfied...

I really couldn't believe it. Even though I sweat a lot, I don't smell at all anymore. Completely odorless. I had a big problem due to a treatment I was undergoing that caused me excessive sweating, and finally I found a solution. It was recommended to me by a pharmacy and it works. It lasts quite a long time. Basically, I apply it 2-3 times a day by wetting it, and I'm good for the whole day.

Although a friend of mine who uses it and is very satisfied recommended it to me (she doesn't use any other deodorant, only this one), it didn't work for me at all. Maybe it's just not right for me, I don't know, because the reviews I read before buying it, as well as my friend's personal opinion after years of using it, were very positive, so I expected more... Maybe it just didn't suit me, but I won't buy it again, I will look for something else

It does a very good job, opens up the pores and helps with sweating, killing the bacteria that cause odor. The only negative, which all crystals have, is that after a certain period of time, the skin gets used to it and it stops working, at least in terms of odor control.

Everything is good with the product, but: it is not clear whether it contains harmful aluminum compounds or not, which are often listed as Potassium alum in small letters. Similar natural crystals from other companies state that they contain it. This specific one...?

All deodorants in crystal form are not suitable for heavy sweating, they may work but not to the extent that there will be no odor. It is a good crystal that lasts a long time, but out of all these alternative deodorants, I would recommend Optima Ice Guard spray as the best. It does a very good job