Crystal Chalk Update

When we first tried out the anti-sweat gel that would become Crystal Chalk we were pretty excited. It was the most powerful non-prescription product against sweating. There were a lot of things to like about it: it was completely transparent & it made the finger skin measurably drier.

But the response when people tried it was pretty polarising: it immediately had big fans but also quite a few people who didn’t like it. And now after more months of testing we figured out what’s going on. And it’s entirely our fault. This post is a mea culpa.

What we did wrong is that we completely fumbled explaining how to actually use the product. Most people used Crystal Chalk like they would normal chalk. But it’s an entirely different kind of product. And it needs to be used in a different way.

Crystal Chalk is part of a category of products called anti-perspirants. These have a different working mechanism than drying agents such as chalk or liquid chalk. To illustrate the difference between drying agents vs. Anti-perspirants we need to have a look at why we sweat.

Sweating is the body’s natural mechanism to regulate body temperature. And we all know that sweat is a climbing athlete’s enemy number one. So what can we do to keep our fingers dry? There’s two ways:

  1. Preventing the sweat from forming in the first place. That is what anti-perspirants like Crystal Chalk do.
  2. Absorbing the sweat after it has been formed. This is what drying agents like Magnesium Carbonate do.


The mistake we made when we introduced Crystal Chalk was to present it as a drying agent, which it is not. And that is because we ignored the early warning signs when we used it ourselves. We noticed that the “drying” effect became stronger as our climbing session progressed. That is because anti-perspirants have a slow-starting but long-lasting effect. The work by cerating a barrier to the sweat glands preventing sweat from appearing on the surface.

And it also explains why people who applied Crystal Chalk in the middle of their session had such a bad experience. The anti-perspirant effect takes a while to start & most importantly: it only prevents new sweat from forming, it does not absorb the sweat that is already there. So applying it to already-sweaty hands in the middle of a session is not the right way to use it.

Here’s the correct way to use it: apply Crystal Chalk 10 to 15 minutes before your first climb, ideally before your warm-up. Then re-apply as needed. The anti-perspirant effect should last about 2h but it depends on the acidity of your skin.

Most people apply a good amount before climbing & then do 2-3 top-ups in the first hour of the climbing session. That should be enough to stop the sweat from forming for most skin types.

Crystal Chalk is dermatologically tested & is safe to use in combination with regular chalk. The ideal way of using it is to use crystal chalk early on in your session and then top up with regular (liquid) chalk near the end of your session.

Some people actually won’t need extra regular magnesium carbonate once they start to use Crystal Chalk. This seems to depend on how sweaty your skin is by nature and the Ph (acidity) of your skin. These factors vary from person to person & the best way to discover what works for you is to try it, and most importantly: apply it 15 minutes before your first climb.

We actually did the experiment & sent out a batch of samples with modified instructions that read “Apply 15 minutes before your first climb”. The complaints mostly disappeared & we received good feedback from routesetters who were stoked that they now could set routes without fouling up the holds with chalk before customers even tried them.

So yeah, we fumbled explaining how to use that product. We’re going to do a bit of a re-branding & update the instructions. Oops. Our mistake. Live and learn.

Photo by Allan Mass