Narvi Split-Face Sauna Stones | 4 to 6 in, 44 lb (With Heater Purchase Only)

Why split-face, and why this size

A sauna stone has two jobs: hold heat, and hand it back to water fast. Split-face stones do the second job better than rounded ones because a fractured surface has more area and more sharp edges for water to break against. They also stack loosely, and the air gaps between them are what let a wood stove draw heat all the way through the pile rather than roasting the outside and leaving the middle cold.

The 4 to 6 inch grade is the large size, meant for the deep baskets on wood-burning stoves. Smaller 2 to 4 inch stones are for electric heaters, where the elements need closer contact. Putting the wrong grade in either one is a common and avoidable mistake.

Olivine diabase

Dense, dark volcanic rock with high heat capacity and a good record of surviving thermal cycling without cracking apart. It is the standard in Finland for a reason, and it is what Narvi ships with their own stoves.

Specifications

• Material: olivine diabase
• Shape: split-face
• Stone size: 4 in to 6 in
• Box weight: 44 lb

How many boxes

Stone capacity is printed in your stove’s manual and it varies a lot between models. Buy to that number, then add a box. Natural stone comes in irregular shapes and you will want to reject a few and choose the ones that seat properly, and having spares on hand at stacking time is the difference between a good stack and a compromise.

Stoves these go in

They suit the large baskets on Narvi’s wood-burning stoves: the Narvi NC, the Narvi Kuru and the Narvi 30.

Restack them

Stones break down. Once a year, pull them all out, throw away anything cracked or crumbling, wash the rest and rebuild the pile loosely. It is an hour of work that people skip for five years and then wonder why the steam went flat.

Call Ben² at (844) 565-1113 if you’d like to talk through the order.