I have been doing face masks of vinegar and benonite clay for some time, I think they work well for red marks and also dragging out impurities. If you do it a few days in a row you can also get a peel effect (depending on how sensitive your skin is etc.).
My latest wonder solution to acne and IBS (gas / bloatedness / pain) is taking benonite clay internally. I have been using it (internally) less than a week so I can’t comment on how well it works long term. I have tried many things for both acne and IBS (including the SCD diet, or a stricter form of it, in which I ONLY and I mean ONLY ate nuts – not peanuts – , eggs and vegetables – not potatoes – for 7 months). Here’s how to prepare bentonite clay (which is available online or most likely in health food shops for a few dollars or pounds and you only use a little at a time).
Mix 5 oz of water with one teaspoon of bentonite clay. Allow it to settle for a few hours or overnight (as you don’t want to be drinking the sediment). Don’t use metal containers or spoons, as it’s bad if metal comes into contact with the clay.
I just use a plastic mug and a plastic spoon, make the mixture, leave it to stand (covering it). I take an average sized gulp in the morning, middle of the day and the evening (I believe you can take it up to 5 times a day but it can have a laxative effect). You have to be careful as you raise the container to your mouth as the sediment on the bottom will quickly mix itself about. When you get too close to the sediment tip it out and make another batch.
Remember to drink on empty stomach and drink plenty of water throughout the day.
Give it a try and let me know how you get on, I believe this is what is helping me but of course you can never be sure as there are always other factors etc.