New Zealand Glacial Clay

May 21, 2022Drew Mitchell

New Zealand Glacial Clay is a high-purity bentonite clay, processed to remove grit and impurities, and sourced from Canterbury in the South Island. It is one of the three active ingredients in our Activated Charcoal Face Scrub, and it is in all four of our shaving soaps.

Ancient Volcanic Ash and Glacial Water

The deposit formed at the foothills of the Southern Alps roughly three million years ago, where ancient volcanic ash met fresh glacial meltwater. That combination produced a nontronite clay, alongside kaolinite, illite and montmorillonite — a mineral profile you don't find in ordinary bentonite.

It is a genuinely local ingredient. There is no substitute for it made anywhere else.

What Bentonite Clay Actually Does

Bentonite is a swelling clay formed from aged volcanic ash. Its platelets carry a net negative surface charge, and the clay has an extremely large surface area for its mass. When hydrated, it swells and those charged surfaces become available.

What follows is adsorption — particles sticking to a surface — and cation exchange, where positively charged ions swap onto the clay. In practice, on skin, that means the clay binds surface oil, dirt and particulate matter, which then rinse away with it.

Clay is often described as "detoxifying" or as drawing toxins out of the body. It doesn't. A clay sitting on the surface of your skin cannot reach your bloodstream, and it has no mechanism for doing so. What it does is bind what's on the surface, which is a smaller claim, and a true one.

Why We Use It

In a face scrub, the clay absorbs excess surface oil and lifts away dead skin loosened by the jojoba beads.

In a shaving soap, it does something different: clay gives the lather slip. A soap with clay in it lets the blade glide rather than drag, which is the difference between a clean shave and a nicked one.

Glacial Clay FAQs

What is New Zealand Glacial Clay?

A high-purity bentonite clay from Canterbury, formed three million years ago where volcanic ash met glacial meltwater at the foot of the Southern Alps.

Does clay draw toxins out of your skin?

No. Bentonite binds oil, dirt and particles sitting on the surface of the skin, through adsorption and cation exchange. It does not remove toxins from your body, and no topical clay can.

What does bentonite clay do in a shaving soap?

It adds slip. Clay in the lather lets the razor glide across the skin rather than dragging on it.

Is bentonite clay safe for sensitive skin?

Bentonite is widely used in cosmetics and is generally well tolerated. As with any new product, patch test on a small area first.

What's the difference between bentonite and kaolin?

Bentonite swells when wet and has a stronger surface charge, so it absorbs more oil. Kaolin is gentler and less absorbent. New Zealand Glacial Clay contains both, along with illite and montmorillonite.