The most durable of the offered in the shops of Minsk, semi-precious stone for the heater. It meets all the requirements and, plus all, has a beneficial effect on the circulatory, nervous system of a person. Has a healing effect for joint pain. Experts in the sauna business will always advise you to purchase a chipped copy to increase the amount of steam offset by a larger evaporation surface. But keep in mind that the price of such a stone is high). Talcochlorite.
Another of the best options for a heater. High heat capacity and heat resistance. A source of light and pleasant steam. From medicinal properties: lowers blood pressure, positively affects the respiratory system, increases immunity, etc. ☝️ The only minus stone can "dust". To avoid this, rinse and burn thoroughly before using it for the first time! Let there be steam!
And this, a fairly rare mineral has a very spectacular color - purple. It has a special density, strength, durability. On a hot stone you can easily pour at least ice water with him nothing will happen.
The most popular option. Diabase is durable, dense, accumulates well, and then gives off heat. An ecologically sound breed is brought from Karelia. For these stones, you can not use essential oils with tinctures - instantaneous build-up of carbon deposits. But the cost is much lower compared to other minerals.
Choose and worry about your health!