Home Cosmetic Science Talk Formulating Clay Masks and pH - How to avoid skin irritation

  • Clay Masks and pH - How to avoid skin irritation

    Posted by Zink on December 7, 2014 at 3:55 pm

    I have recently been formulating a french green clay mask, and noticed it makes the skin red if leaving it on for too long. It’s a temporary redness, but not a feature people appreciate, even though I hear this is ‘normal’ with clay masks. Turns out it’s the clay itself causing the redness, and I hypothesized it was due to their basic pH.


    I found a Reddit discussion where a list of Clay pHs was posted http://www.reddit.com/r/SkincareAddiction/comments/19i8w1/psa_aztec_secret_aka_calcium_bentonite_clay/  (no references):

    Calcium Bentonite (aka Aztec Secret): 8 - 9.7

    French Green (aka Illite Clay or Sea Clay): 7.75

    Fuller’s Earth: 7.5

    Rhassoul (aka Red Moroccan or Red Clay): 7 - 7.5

    Dead Sea Mud: 7

    Kaolin (all colors): 6

    Moor Mud: 4.5 - 5.5

    I’m not sure if these numbers are correct or if it’s even a valid measure, but I have noticed that french green clays cause more irritation than kaolin clay, and using apple cider vinegar to neutralize the pH makes the former less irritating. 

    For a french green clay mask, are there any ways to make it less irritating without losing it’s oil drawing powers? Adding e.g. citric acid to balance the pH? Adding oils does help, but that seems to defeat the purpose of the mask.

    PSA: Aztec Secret (aka calcium bentonite clay) should be mixed with raw apple cider vinegar, not water.
    byu/valentinedoux inSkincareAddiction

    yongnn30 replied 9 years, 11 months ago 4 Members · 5 Replies
  • 5 Replies
  • heraklit

    Member
    December 7, 2014 at 5:41 pm

    I don’t have experience on green clay but i know that most clays and muds causes temporary skin redness due to local hyperaemia from their texture or heat - that’s why they temporary relieve joint or muscle pains. It’s not clear that irritation is due to pH, some people have irritations with clays or muds, many people no, but of course you can drop the pH with citric acid

  • yongnn30

    Member
    December 7, 2014 at 7:43 pm

    My experience on doing Clay Mask (a few years ago) using White Clay form Malaysia.. I try to maintain pH at pH6.5 and I’m using 0.5% alllantoin and 0.6% Portulaca Oleracia Extract as anti -sensitive agent… feed back from my customer, they like the texture and it works on sensitive ski

  • ozgirl

    Member
    December 7, 2014 at 8:55 pm

    Can you substitute some of the French Green Clay with the lower pH Kaolin? This might reduce the irritancy.

  • Zink

    Member
    December 8, 2014 at 2:53 am

    Using some Kaolin clay helps, but I want to stick to “oil drawing” clays for this formula, allegedly Kaolin clay does not have that property.

  • yongnn30

    Member
    December 8, 2014 at 4:22 am

    @Zink..maybe you can add binders/emulsifier..

    Emullium delta from Gatte Fosse..it’s compatible to high pH

Log in to reply.

Chemists Corner