I bought this mineral clay mask from Wal-Mart for around six dollars and I really love it! Honestly, I am a big fan of a lot of St. Ives products already, so I wasn't surprised to like this too.
The back of the tube says, "this mask, with kaolin clay, deep cleans while visibly firming and tightening the skin". The directions say, "to use when you need an extra deep clean. Begin by cleansing face. Apply a thin and even layer to skin avoiding eyes, lips, and hair. Once mask is completely dry (10-15 minutes), rinse with water. In case of contact with eyes, flush throughly with water.
I find this mask to be very refreshing and relaxing at the same time. I love the way it smells fresh and minty and feels tingly on the skin. There was a point when I first used this product where I was a little concerned that my skin was burning and that I would have to wash it off, leaving my skin red and irritated, but I washed off a little area and it looked good, so I stuck with it and I am glad because my skin loves it. I consider myself to have pretty sensitive skin too!
I also love the way when it dries it really tightens around my face pulling everything in. I try to stay away from anything that will make me laugh to avoid getting the smile lines while the mask is drying. It is nice to just sit down, listen to some music and moisturize my hands, feet and body while waiting for the mask to dry. I find it takes longer than 10-15 minutes, I would give it 20-30 minutes to fully dry before washing it off. When I wash it off my face feels invigorated and super soft, and looks clean and shiny :)
I looked it up and apparently, kaolin clay, which is composed of aluminum oxide and silica, has the ability to dry the skin, fighting acne, as well as increasing localized circulation, which can help to fight inflammation. It is likely that the tightening effect that you feel after using the mask is caused by the moisture that is removed from the skin. Kaolin clay is also used in makeup to stop powder based formulas from caking. The ingredients also list Rosemary leaf extract, caffeine and ginkgo biloba leaf extract, which probably contribute to the nice smell, decreased inflammation and feeling of softness after.