Silica Silylate in Climbing

Introduction

There’s a new wave of “chalkless” grip products making the rounds in the climbing community. At the center of many of these products is silica silylate, a fine, hydrophobic powder originally used in cosmetics and personal care. Products like Rungne’s Maglock, designed specifically for climbers, and Chalkless, which targets a broader range of grip athletes, have brought this ingredient into the spotlight.

Bottom line: while silica silylate is technically safe according to safety data sheets (SDS), using it in powder form for climbing just doesn’t make sense. There are cleaner, safer, and more effective alternatives.

TLDR; At Chalk Rebels, we looked into using silica in climbing chalk over three years ago. After testing and research, we decided against it—at least in powder form. Instead, we found that gel-based formulations worked better and posed fewer risks.

What Is Silica Silylate?

Silica silylate is a synthetic, amorphous form of silica. It’s designed to repel water (hydrophobic) and bind to oils (lipophilic), which makes it useful in all sorts of cosmetic applications like anti-shine face powders and anti-perspirant gels.

In climbing, it’s used for the same reason: to help keep your hands dry by pushing moisture away from the skin.

Often Confused with Crystalline Silica

• Crystalline silica (like quartz dust) is a known carcinogen and can cause silicosis, a deadly lung disease.
• Amorphous silica like silylate isn’t carcinogenic, but it’s still classified as an airborne irritant.
• The two are chemically related, and they’re often confused.
• Poor-quality suppliers can introduce trace crystalline silica into otherwise safe products.

How It Works in Climbing

Silica silylate repels water. When applied to the skin, it pushes sweat and moisture away. That moisture doesn’t disappear—it usually gets absorbed by your chalk. Chalk is hydrophilic, meaning it attracts water. But once chalk becomes saturated, it stops working. That’s when your grip starts to feel slick and unreliable. That's when you chalk up again.

Silica silylate also binds to skin oils. When applied in gel form, it adheres well to the skin, forming a stable, even layer. This makes it a “leave-no-trace” grip enhancer with minimal residue left on holds or in the air.

Brands like Metolius used silica powder in the past for exactly these reasons, though most now have removed these products from sale.

A Look Back: Who’s Used It Before?

• Metolius included silica in Super Chalk and Eco Ball, but reformulated them later.
• Spider Chalk used it in Ghost Grip and is now being sued by Chalkless, Inc.
• Chalkless holds a U.S. patent on its shaker-style silica-based grip products.

Although silica has appeared in various climbing products, most companies are now backing away from using it in powder form.

Is It Safe?

Silica Silylate

• TWA (Time-Weighted Average): 6 mg/m³
• Not carcinogenic, but still an irritant.
• Easily airborne, especially in enclosed spaces like climbing gyms.
• No long-term safety data for regular use in climbing environments.

Chalk (Magnesium Carbonate)

• TWA: 15 mg/m³
• Long history of use and relatively well understood.
• Gyms often exceed safe exposure levels without proper ventilation.

Other Indoor Airborne Contaminants

Climbing gyms also contain dust from rubber abrasion and adhesives. These add to the air pollution already present. Adding silica powder on top of that isn’t helping anyone.

Powder vs. Gel: A Clear Difference

Powder Form

• Ultra-fine and easily airborne.
• Up to 80% product waste when applying.
• Can cause skin irritation & make small skin cuts worse.
• Contributes to indoor dust.

Gel Form

• Silica is bound in a liquid, so no dust when applying.
• Controlled, even application.
• Often made under cosmetic GMP and tested dermatologically.

Silica silylate binds to oils but doesn’t remove them. Alcohol-based products, like liquid chalk, actually clean and remove oil from the skin. That’s why they work better as a base layer.

Field Testing: How It Actually Performed

We tested four silica-based grip products: a Chalkless-style powder from China, generic silica powder, a hair product with silica, and our own gel-based primer.

They all dried the skin to some degree, but the powders were messy, wasteful, and rough—most of the product just floated off into the air. The hair product worked okay but felt waxy and inconsistent.

The gel stood out: smooth, controlled, and clean. It took a little longer to dry compared to the powders, but once it set, it bound better to the skin and lasted longer. It also felt less aggressive. More skin-friendly overall. For real climbing use, it was easily the most practical option.

Industry Trends and Legal Issues

Chalkless, Inc.

This U.S. brand markets shaker-style silica grip and holds a relevant U.S. patent. They’ve expanded into adjacent sports like CrossFit and esports.

Legal Action

In 2025, Chalkless sued Spider Chalk over packaging and formulation similarities.

Transparency and Sourcing

We’ve seen inconsistencies in SDS documents from Chinese suppliers. European-made gels generally meet higher safety standards.

So. Is It Worth It?

Silica silylate isn’t evil. But using it in powder form for climbing is hard to justify. It creates dust, wastes product, and poses a potential health risk in already dusty gym environments. And better options are out there.

Better Alternatives Exist

1. Use Alcohol to Remove Oils

Liquid chalk removes oil and dries the skin. Silica just binds to oil—it doesn’t clean anything.

2. Use Upsalite to Absorb Moisture

Upsalite is a mesoporous magnesium carbonate that absorbs water far better than silica. It performs better and leaves less mess.

3. Still Want Silica? Use It in Gel Form

Gel-based silica products offer all the benefits—without the dust. They’re safer for your skin and your gym partners.

Final Word

We already have cleaner, safer, and more effective tools for grip. Let’s not trade decades of chalk experience for short-term novelty—especially when it brings more questions than answers.