Introduction
Open Formula might not have reached household name status yet, but skin care circles know it for formulas that lean on simplicity and science. That reputation alone made me curious enough to scoop up their Bentonite Clay Mask, a product whose name leaves zero room for mystery: clay, clay and more clay.
According to the brand, this wash-off mask is aimed at tackling blemishes acne scars and those pesky enlarged pores while giving you an at-home facial experience. The routine is straightforward: cleanse, blend equal parts of powder and liquid, spread the paste, wait 10 to 20 minutes then rinse and follow with moisturizer. Use it once or twice a week and it should help clarify and refine skin without disrupting the rest of your regimen.
I spent two full weeks coaxing my complexion through several sessions to see if this mineral-rich mask could live up to its rather bold promises and whether it deserves a spot in your bathroom cabinet or just a fleeting mention in group chats.
What is bentonite clay mask?
This product is a single ingredient powder made of bentonite, a mineral rich clay that becomes a paste when you blend it with water or another liquid. Open Formula positions it as a treatment for blemishes, acne scars and enlarged pores, to be used after cleansing and before moisturizer.
Technically it sits in the wash-off mask category. That means it is designed for short contact with the skin, letting the formula do its work before you rinse it away. Wash-off masks are popular because they deliver a more intensive hit of active ingredients without leaving anything behind that could clog pores or interfere with the rest of your routine.
In practical terms you scoop equal parts powder and liquid into a bowl, spread the mixture over clean skin, wait up to 20 minutes then remove it with water. Because bentonite is naturally absorbent the mask tightens as it dries, which helps draw out excess oil and surface impurities. The brand advises limiting use to once or twice a week to avoid over-drying and always following with a moisturizer to replace lost hydration.
Did it work?
I shelved my usual wash off mask for the sake of science, or at least my best impression of it, and gave this clay my full attention for 14 days. That felt like a fair window to see real change without drifting into placebo territory.
Session one started with a one to one mix of powder and water. The paste went on cool and thick, tightening almost immediately. Ten minutes in my cheeks felt like they were shrink wrapped, so I rinsed at the fifteen minute mark. Post rinse my skin looked brighter and felt smoother, though it also felt a little thirsty until moisturizer stepped in.
For the next two weeks I repeated the ritual every third day, clocking five applications in total. By round three I noticed midday shine backing off, especially around my nose and chin. A couple of angry whiteheads calmed faster than usual but existing acne scars stayed stubborn. Pore size looked slightly refined after each use yet the effect faded within 24 hours, suggesting the clay was mopping up surface oil rather than rewriting my skin’s blueprint.
On the flip side those with drier patches should tread lightly. The mask left a faint tightness that lingered even after moisturizer on the evenings I pushed the full twenty minutes. Dropping to twelve kept the balance better without losing the clarifying hit.
So did it live up to its promises? Partly. It definitely soaked up excess oil and gave a fleeting sense of refined pores. Blemishes looked less inflamed but scars did not budge. Will I slot it into my permanent lineup? Probably not, though I can see myself reaching for it the night before a big event when I want an instant, if temporary, reset.
Main ingredients explained
This mask keeps things gloriously simple with one star component: bentonite clay. Bentonite is a naturally occurring mineral clay formed from volcanic ash that is rich in montmorillonite, magnesium, calcium and trace elements. When it meets water the clay particles swell then create a negative charge that attracts positively charged impurities like excess sebum and pollution residue. That ionic swap is what gives the mask its oil-mopping, pore-clarifying reputation.
Because the formula is literally just powdered clay it is automatically free of animal derivatives, making it suitable for vegans and vegetarians. Bentonite also ranks very low on the comedogenic scale, sitting around a 1 out of 5, meaning it is unlikely to clog pores. (A comedogenic ingredient is one that tends to block follicles and trigger breakouts.)
There are no added fragrances, dyes or preservatives so the risk of irritation comes mainly from the clay’s strong absorbency; leave it on too long and it can pull water out of the skin along with oil. Sensitive types might want to mix it with a hydrating liquid like aloe juice instead of plain water to soften the blow.
Pregnancy safety is generally good with inert minerals like bentonite, yet dermatologists still advise running any new topical past your doctor while expecting or nursing. One final note: clays mined from the earth can carry trace heavy metals, though reputable brands test batches to keep levels well below regulatory limits. If you have metal sensitivities it is worth asking the company for their latest lab data.
What I liked/didn’t like
After five sessions these are the clear pros and cons.
What works well:
- Single ingredient formula keeps potential irritants to a minimum and plays nicely with most routines
- Noticeably mops up oil and leaves pores looking tighter for a short window
- Mix-it-yourself flexibility lets you tweak thickness or add soothing liquids like aloe juice
What to consider:
- Refined pore look is temporary so the payoff hinges on consistent use
- Can leave skin feeling dry or tight, especially if left on the full 20 minutes
- Needs mixing before each application which adds an extra step compared with pre blended masks
My final thoughts
After five rounds I landed on a solid 7/10 for Open Formula’s Bentonite Clay Mask. It earns that score by doing exactly what a classic clay treatment should: drink up oil, give pores a fleetingly tighter look and calm inflamed breakouts faster than my regular cleanser can manage on its own. If you have combination or oily skin that misbehaves before big meetings or nights out this is an easy grab. If your concerns lean more toward lingering acne scars, deep congestion or dryness you will probably want something with added exfoliating acids or soothing agents instead.
Would I recommend it to a friend? Yes, but with caveats. I would hand it over to my shine-prone pals who enjoy the ritual of mixing a mask and do not mind a result that lasts about a day. I would steer my Sahara-dry friends away and tell the severely blemish-prone crowd to pair it with a targeted spot treatment for best results. I have tried dozens of wash-off masks over the years and I feel confident I gave this one its fair shot before coming to that conclusion.
If you like the idea of a quick pore reboot yet want a bit more multitasking power, there are some excellent alternatives I have rotated through my own bathroom. Deascal’s Pink Clay Glow Mask is an uncomplicated allrounder that exfoliates, clears pores, brightens and generally makes skin look like it slept eight hours; it suits every skin type and the price feels almost too kind for how effective it is. Caudalie’s Instant Detox Mask gives a similar oil-absorbing hit but folds in grape polyphenols for added antioxidant support. Innisfree’s Super Volcanic Pore Clay Mask offers micro-volcanic clusters that leave skin feeling extra smooth without over-stripping. On budget days The Ordinary’s Salicylic Acid 2% Masque combines clay with a gentle BHA to keep breakouts at bay while still delivering that satisfying post-mask matte finish.
Before you slather anything new on your face, remember a few boring yet important realities. Do a patch test on your jawline or behind the ear first (sorry for sounding like an over-protective parent). Accept that any pore-shrinking magic is temporary and that consistency, not a single session, keeps results ticking along. With that in mind happy masking and may your T-zone stay calm and collected.