Which stones are best to choose for a bath: types of stones and their characteristics + recommendations for use

When the construction and finishing of your own steam room is completed, all that remains is to choose the best stones. But the assortment offered by the market is rich, and you don’t really want to take the first ones you come across, do you?

We will help you figure out which stones are best to choose for a bath, so that they do not disappoint you during operation - the article discusses the main characteristics of various types of stones and their advantages when used.

After all, a lot depends on your choice: the speed of heating the room, the time for maintaining high temperatures and the aesthetic appearance of the stove itself.

Criteria for choosing fillers for the stove

You can design the heater yourself if you have time to search for suitable stones, or purchase a ready-made kit in the store.

But not every breed will adequately withstand the peculiarities of the sauna microclimate, so let’s consider the main characteristics that you need to pay attention to when choosing a filler for the stove.

Heat resistance, strength and structure

The main purpose of bath stones is to heat up quickly and retain heat for as long as possible. Not only its service life, but also the amount of steam, fuel consumption for the stove and the overall comfort of staying in the bathhouse directly depend on the heat capacity and heat resistance of the filler.

The “correct” stones can be identified upon inspection - they will have a non-porous structure and a high specific gravity.

Heat-resistant rocks, for example, dunite or jade, can last a decade, but the average lifespan of most stones is 3-4 years, after which the rock begins to crumble, smoke and dust.

The higher the density of the rock, the better the stone tolerates temperature changes in the steam room, warms up faster and cools down more slowly

To test the strength of the stones, you can hit them with a metal hammer or against each other - if the sound is dull, such a filler will not last long

It is important that the material is homogeneous, without any foreign inclusions, because they can cause the stone to explode at high temperatures.

Experienced bathhouse attendants have a great way to determine which stones are ideal for a steam room in a bathhouse, but you can only use it in practice: heat it red-hot and throw it into cold water.

A truly high-quality filler will easily withstand this test without forming cracks or splits.

Optimal size and weight of stones

The size of the stones directly depends on the type of sauna stove, so they need to be chosen practically, guided not only by design considerations.

For example, for a sauna with an open heater, which heats the air to 100 degrees and above, you should use only large and medium format samples.

The best shape is rounded pebbles that are smooth to the touch - they will produce less debris, and they look more aesthetically pleasing than chipped rock fragments

For electric heater choose small pebbles with a diameter of 4-6 cm, and the stones must be well polished so that their sharp edges do not deform the heating element.

In a wood-burning stove, specimens of the medium and large fraction, 6-18 cm in size, will last longer. Small stones are not used here so as not to block the openings of the stove grate.

The amount of filler is selected individually, based on the size of the room and the type of oven. If there are not enough stones, the sauna will not warm up well, despite the increased fuel consumption. With a large load, the heater will produce intense steam and heat, in which not every bathhouse attendant will be comfortable.

The instructions for purchased heaters must indicate the recommended weight and fraction of stones. For homemade saunas, you can focus on average figures: per 1 m² the room requires about 6 kg of stone.

In closed heaters, cast iron cores or other inexpensive fillers with good heat transfer are often used, decorating only the upper layers with natural minerals

For classic bath with a closed oven, the dimensions of the filler depend on the size of the door designed to supply water. Here, grinding is not so important, the main thing is that the stones pass freely through the hole and are compactly located inside.

Environmental safety of the filler

If our ancestors could collect stones for a steam room without thinking about environmental problems, then in modern realities such savings can be costly.

For example, you should not take various stones from the embankment near the railway for a sauna stove - they can be treated with creosote. This chemical does not erode or wash away and turns into a toxic vapor when heated. The same applies to cobblestones from construction sites or dumps.

The most budget-friendly filler for a stove is river or sea pebbles, but with regular use of a bathhouse, such stones quickly break down and need to be regularly inspected and replaced.

Do not forget that natural material may contain radionuclides, for example, granite. Therefore, the safest option would be to buy stones in specialized stores. In this case, you will be sure that the product has passed radiation control.

However, you can safely buy rocks that were formed at great depths, such as peridotite, jadeite or dunite - they cannot contain radioactive elements.

Types of bath stones

To decorate your bath, you can choose any filling from an impressive range of stores selling bath products. Each breed has its own “zest” - this could be a long service life, spectacular appearance or special lithotherapeutic properties.

Group #1 - semi-precious rocks

You can decorate the design of your heater using beautiful semi-precious stones. Adherents of lithotherapy claim that the addition of such fillers to the bookmark greatly enhances the healing effect of the sauna, turning it into a universal remedy for many diseases.

The most common of semi-precious minerals is jade. It improves the condition of the kidneys and nervous system, equalizes blood pressure, and restores the bronchopulmonary and musculoskeletal system.

Jadeite is an ideal stone for a sauna stove, valued for its pleasant emerald hue, high therapeutic effect, heat resistance and exceptional strength.

Unique properties of jadeite:

• evenly contracts and expands when heated, without forming cracks or splits;
• has high density and low thermal conductivity, due to which it is able to release accumulated heat over a long period of time;
• disinfects and saturates water with metasilicic acid;
• enriches the air with Zn, Cu, Se, Ag ions.

The price per kilogram of fine crushed jadeite is about 140 rubles. Boned or polished will cost more - from 180 rubles/kg, depending on the fraction and quality of processing.

Regular visits to a bath with jade stones will help equalize blood pressure, improve heart rate, cleanse the body of toxins, improve metabolism and brain function.

Nephritis - another popular semi-precious stone from the pyroxene group. Like jadeite, this mineral has high strength and excellent heat retention.

As for color, much depends on the presence of various impurities in the composition of the stone. Although we expect jade to have a green hue, a rock enriched with magnesium can be pink, while iron can be black or dark brown. A bright emerald color is a sign of the presence of chromium.

Jade has long been valued for its high healing properties - in the East it is considered a panacea for all diseases and is called the “stone of health.” But the cost of such a universal healer is impressive - from 300 rubles / kg.

By the way, the high price of jade has given rise to many fakes - unscrupulous sellers sometimes pass off an ordinary coil as an expensive bath stone, which has low strength and will not last long in a steam room.

Upon inspection, the coil is easy to identify - it splits without much effort when hit with a hammer and is scratched with a knife, which cannot be said about jade

No less popular jasper - a red-brown semi-precious stone with a wide range of healing properties and excellent heat transfer.

A bath with jasper bookmark helps heal the reproductive and nervous system, helps fight headaches, depression, insomnia and promotes rapid healing of wounds. The price per kilogram of stones starts from 170 rubles.

Group #2 - artificial stones and cores

Since natural materials are quite expensive, various mixtures can be used to lay the heater.

The basis of such a mix can be any stones with good thermal conductivity, including artificial fillers. And you can supplement and decorate the total mass with several species with healing properties.

The simplest filler is cast iron, which has long been used for camp stoves, and it is from this that the famous expression “vigorous steam” originated.

Cast iron cores, cones or shells quickly heat up on their own and are great for large rooms, because the thermal conductivity of metal is 30 times higher than that of natural stones.

The steam from such elements turns out to be really vigorous - very hot and dry, so it is recommended to add stones to the bookmark. But such a filler is guaranteed not to crack at high temperatures and will continuously serve for many years.

Imperial or royal porcelain is a beautiful artificial filler in the form of white balls, the strength of which is comparable to natural diamond

Another popular and inexpensive filler looks more aesthetically pleasing - ceramic balls. They are obtained by sintering a mixture of white clay, animal bones, quartz and feldspar.

After several firings, all organic impurities from the substance evaporate, and the resulting spheres can easily withstand temperature changes in the baths, have a high heat capacity (up to 1100 J) and provide light steam.

Popular minerals and their comparison

Minerals of volcanic origin are recognized as the best filler for sauna stoves. When heated, they emit infrared radiation, easily withstand significant temperature changes and enrich the steam room air with microelements beneficial to health.

Let's look at the most popular types and their characteristics in the table and compare them with each other.

As for the price, the most budget-friendly among natural fillers will be gabbro-diabase And basalt (25-30 rubles per 1 kg). It will cost the most quartz — from 60 rub/kg.

Operating rules and advice from bathhouse attendants

It’s not enough to just choose the right stones, because you also need to position them correctly in the oven so that the heat is comfortable and the steam is fine and really light.

Also no less important arrange proper ventilation in a room with an electric heater or another type of stove.

In the masonry, it is necessary to provide a sufficient number of unfilled vertical channels through which hot air will circulate

Nuances of filling the stove:

1. Before installation, the filler must be thoroughly washed and dried.
2. The lower layers are laid in large fragments, which accumulate heat well. It can be peridotite, soapstone, gabbro-diabase, basalt or cast iron cores.
3. Medium and small particles of jadeite, quartzite, jade or other rocks with suitable healing properties are placed on top.
4. The stones need to be placed fairly tightly, but not compacted. After laying, the proportion of air gaps should be approximately 10-15 percent of the total volume.
5. There is no need to place the filler close to the tubes and other elements of the electric heater - when heated, the stone expands and can deform the device.
6. You can only pour hot water onto the heater, in small portions and without additives like honey, oils or beer, otherwise the stones will quickly become covered with soot and will smoke. If you can’t imagine a sauna without aromatic steam, simply dissolve the mixture in water, pour it into a metal bowl and place it on top or hang it over the stove for evaporation.
7. Porphyrite and other rocks may crack slightly when first heated - this is normal. But if the crackling sound is heard constantly, the stones should be reconsidered and, if necessary, replaced - perhaps you received heterogeneous specimens with foreign impurities.

And lastly: do not forget to check the condition of the heater at least once a year and check the filler for cracks and breaks.

Damaged stones must be removed and replaced with new ones, and those that have adequately withstood the test of heat and steam must be washed under running water and sent back to service.

Conclusions and useful video on the topic

If you still can’t decide which stone is best to choose for your steam room, we recommend that you familiarize yourself with our selection of videos.

Tips for choosing bath stones from a heating engineer:

An example of a combined furnace filling with soap chloride and crimson quartzite:

Despite the excellent thermal characteristics of many rocks, we should not forget that the mineral composition of stones can vary significantly depending on their deposit and variable factors.

Therefore, people knowledgeable in the bath business recommend always looking at specific samples of the material, and not just at the name. And ideally, choose a filler with a person who understands the geology and structure of the stone.

What stones do you use? Share your secrets with other visitors to our site. Or maybe you want to supplement the above material with useful recommendations for caring for stones or using them? Express your opinion in the comments to this article.