Chalk

for

Climbing

&

Bouldering:

The

Ultimate

Guide

Although originally known for its frequent use in gymnastics, chalk quickly became the go-to choice for climbers and boulderers, starting in the 70s. Chalk, also known as magnesia (alba) or gym / climbing chalk, is created by mixing magnesium carbonate (MgCO3) with water or magnesium hydroxide – a deliquescent substance, which means it actively attracts and binds moisture. As such, it effectively absorbs the sweat on your palms for a more stabilized and improved grip – which comes in pretty handy when climbing. So whether you're navigating slopers or naked rock, you’ll always have a firm hold on things, and can significantly reduce the risk of injury.

What is climbing chalk made of?

Magnesium carbonate naturally occurs as magnesite (bitter spar) in rocks and stone. After mining, the rocks are then chemically processed to extract the substance. This method is mainly used for sport-related products, while food and pharmaceutical industries commonly rely on a synthetic process called desalination of seawater, where magnesium carbonate is created as a byproduct.

What types of climbing chalk are there?

Whether bouldering or (rock) climbing, everyone has their own personal preference when it comes to chalk – which is why there are several different options to choose from:

• Chalk powder

• Chalk balls

• Liquid chalk

• Chalk with various additives

• Eco chalk, aka the eco-friendly alternative

Chalk powder

Typically, chalk is sold in plastic bags as loose powder, but can be easily poured into a chalk bag. Chalk bags are usually either fitted with practical hip straps, or can be attached to the back of your climbing harness ↗, allowing you to dip in your hands whenever – and wherever – you need. Chalk is available in different consistencies too, ranging from coarse to extra fine powder.

Pros: You can quickly apply it in large quantities and it’s reasonably cheap. Plus, it works for any type of climbing activity.

Cons: It creates a lot of dust, and getting the quantity exactly right can be tricky. It’s pretty normal for powder to literally fly everywhere when you’re trying to cover your palms – and it may even get in your eye while you’re belaying.

Good to know: When using a chalk bag, always make sure to fully empty it at regular intervals. Otherwise, you may end up with small, hard chunks at the bottom instead of powder.

Chalk with various additives

To ensure a particularly smooth experience while weightlifting or doing exercises in artistic gymnastics, traditional magnesia is often laced with talcum powder to further reduce friction, ensuring the skin is as smooth as possible and won’t stick to any surface. Again, not exactly practical for climbing, where a good grip is key.

As an alternative to traditional climbing chalk, there are some chalks with various additives like desiccants for powdered chalk, and resins like colophony for liquid chalk. Some desiccants like silicates or mesoporous magnesium carbonates (also known as Upsalite) may not be suitable for sensitive skin, so it’s best to try a number of different products first before getting yourself that super-sized value pack. Pure colophony is often the recommended substitute for liquid chalk when climbing outdoors. In France, it’s also known as Pof, and is frequently used in regions like Fontainebleau, where the use of regular chalk is strictly prohibited. On the flip side, it can be damaging to some types of rock, for example limestone. It also has widely disappeared from indoor climbing venues because it leaves a sticky coating on slopers and handles. That’s why a number of brands are now opting to sell colophony-free, environmentally-friendly chalk.

Eco chalk

Some manufacturers carry eco chalk. However, the term itself is not trademarked, so ingredients often vary from product to product. In some cases, these products are synthetically produced and sold under the label “pure” or “eco”. Another alternative is chalk made from wholly different matter, for example Carbosil or silica. It’s especially useful when climbing outdoors, as it doesn’t leave white spots, and neither affects the rock surface.

Finding the perfect chalk for your climbing style

The best chalk for bouldering

You want to make the most of your dexterity? Then chalk balls – aka the classic, less dusty variant – are the way to go. They will help you get the amount exactly right – for perfect grip indoors and outdoors. If you’re looking to try out moves with a high difficulty level or want to conquer particularly tricky slopers or pinches, an extra layer of liquid chalk will go a long way.

More grip: The best chalk for (rock) climbing

When it comes to climbing, the choice of chalk depends entirely on the length of your route. For short to medium-length routes, you should carry a chalk bag with chalk powder or chalk balls so you can easily re-apply it even when you’re in the middle of climbing. On longer routes, it’s best to use liquid chalk as an extra dry base before topping it up and fortifying it with powder at regular intervals throughout your climb.

Tips for indoor climbing

When climbing indoors, you should use liquid chalk or a chalk ball to keep dust formation at a minimum. Many venues have even taken to putting up “No dust” signs to combat fine dust pollution: Not only does the use of chalk powder negatively impact air quality, it also makes slopers and grips super oily. Come closing time, the contaminated spots usually can only be cleaned with high-pressure cleaners or special cleaning agents.

Environment first: Chalk for outdoor climbing

Before scaling the most exciting rocks out there you should find out if using chalk is actually permitted. In some regions, its use is strictly forbidden in designated areas, while some regions in Europe have banned the use of chalk altogether. One of the reasons? The white markings on the rocks immediately give away the betas. Additionally, there’s the environment to consider: Chalk can have a negative impact on vegetation, from stunting the growth of various plants to causing them to die back. Even a minimal amount of the magnesium carbonate mix will draw any moisture nearby into the smallest fissures on the rock, where it freezes when temperatures plummet, ultimately leading to congelifraction. As a result, the rock will get crumbly – especially limestone. An excessive amount of chalk will also accumulate on the surface and eventually create a thick layer of dirt, which in turn makes the rock slippery and dangerous to climb. Some climbers then apply even more chalk to get a somewhat decent grip – and the vicious circle is complete. So when you’ve completed your route, it’s best to simply brush off all traces of the white stuff. Special brushes will help you to effectively remove any residue, while at the same time being gentle to the surface. As a general rule, though: Go easy on the chalk.