Konjac sponges are all over the beauty market these days but they're a very old idea. First made and used iin Japan specifically for washing babies because they're especially soft, it's easy to see why thier properites made them appealing - add in the easily renewable angle and we're all over it. Kojac is a plant that has an edible corm and it's thos corm part that's pulped to make the sponge. Which is all very clever in itself and then someone had the bright idea to mix it at that stage with things like clays and activated charcoal, which jusst brought it up to another level. The idea is that you can cleanse with the sponge, while it imparts all the benefits of purifying clays or clarifying charcoal to your skin, then when the sponge has had it's day, which it will because it's a natrual prodcut. then you just pop it into your home compost.
I like them because they're great for removing the last traces of my mascara without dragging the skin under my eyes and I like them cool soft feeling of them on my skin. I've been using mine for about five months now and I don't know if I'm esecially gentle on them, but it's not falling apart yet. I am careful to hang it up and let it dry in between uses though, I think that helps.