15 Jun 2026
The Alpenkraft «Steinmatte» is a bath mat made of Kieselgur (diatomaceous earth), not fabric. You step out of the shower onto a hard, slightly porous stone slab; it pulls the water off your feet and into its pores, then the surface is dry again in seconds. The pitch is simple: no soggy textile mat, no mould, less cleaning. It comes from Alpenkraft (the same Austrian shop behind the ZugSpitze shower head). Below are the facts from the product page, with manufacturer claims flagged as such.
What it is
Diatomaceous earth is a soft, porous sedimentary rock made from fossilised diatoms (single-celled algae). Pressed into a slab, it acts like a stone sponge: water wicks into the microscopic pores fast, spreads through the material, and evaporates off the large surface. That is why the top feels dry again almost immediately after you stand on it, unlike a cloth mat that holds the water against the floor.
Alpenkraft sells it as the Kieselgur Steinmatte XXL, in one size and two colours.
| Material | 100% Kieselgur (diatomaceous earth), per the maker |
| Size | 70 cm x 45 cm x 0,9 cm (one XXL size) |
| Colours | "Eisbär" (white) and "Mondboden" (grey) |
| Price | EUR 79,90 (listed regular price EUR 109,95) |
| Maker | Alpenkraft (AVM Online Handels GmbH, Austria) |
| Shipping | Free from Austria, per the maker |
| Trial | 30-day money-back guarantee |
How it works
- Absorbs fast. Water soaks into the pores on contact. Alpenkraft says the surface is dry again "in seconds" (in Sekunden).
- Dries itself. The absorbed water spreads through the slab and evaporates, so the mat is ready for the next person without wringing or hanging.
- Anti-slip. The hard textured surface is sold as rutschfest (slip-resistant) for wet feet, a safety angle over a sliding cloth mat.
- Anti-mould / hygienic. Because it does not stay wet, Alpenkraft claims 99% less germ formation (99% weniger Keime) and no musty smell. The logic is sound, a surface that dries quickly gives bacteria and mould less to work with, but the exact 99% figure is the maker's own number, not independently verified here.
- Breathable, skin-friendly. Described as a natural, breathable material, "100% skin-compatible" (hautverträglich). Reviews on the page also call it soft underfoot.
Care
This is the part that differs most from a normal mat.
- No washing. It never goes in the laundry. The maker's line: "Muss nicht gewaschen werden."
- Sand it instead. Stains or worn patches are removed by lightly sanding the surface with the included sandpaper (Schleifpapier), which also reopens the pores so absorption stays strong.
- Longevity. Alpenkraft says it lasts for years with this minimal upkeep.
The videos
Three videos are embedded on the product page. The first two are Alpenkraft's own hosted clips showing the mat absorbing water; the third is the product's vertical demo on Vimeo.
Absorption demo 1 (Alpenkraft, hosted):
Absorption demo 2 (Alpenkraft, hosted):
Product demo (Vimeo, vertical):
My take
The physics is real. Diatomaceous earth is genuinely absorbent and dries fast, so the core benefit, a mat that is dry seconds after you step off and never goes musty, is the honest selling point, not marketing. Treat the round numbers (99% fewer germs) as the maker's claims. The trade-offs to expect with any stone mat: it is rigid and can crack if dropped, it can feel cold underfoot, and the "care" is occasional sanding rather than a wash. At EUR 79,90 it is priced as a premium item for what is, physically, a slab of pressed rock. If a constantly damp textile mat is the annoyance you want gone, this solves it directly.
Further reading
The official product page (German, prices in EUR):
