Zeolite Glossary: The most important terms related to zeolite & soil care, simply explained

Anyone who deals with zeolite quickly encounters terms such as cation exchange capacity, adsorption, or tribomechanical activation – and wonders: What does that actually mean? This glossary explains the most important technical terms related to zeolite, soil science, and minerals in a way that is truly – hopefully – understandable. No scientific jargon, no unnecessary complexity – just clear explanations to help you better understand zeolite and use it more effectively.

A

Absorption 
Absorption refers to the complete uptake of a substance into a material – the substance virtually disappears into its interior and is bound there. A classic example is a sponge that soaks up water: the water is inside but no longer freely available on the surface. In soil, absorption refers to, for instance, the uptake of water into clay particles. The crucial difference to adsorption: what is absorbed cannot be released again in a controlled manner without further ado.

Adsorption
Adsorption, in contrast, refers to the accumulation of substances on a surface – not inside a material, but on its outer or pore walls. Adsorbed substances adhere to the surface but can also be detached and released in a controlled manner under altered conditions. This is precisely what makes adsorption so valuable: it is reversible and controllable.

Zeolite works exclusively through adsorption: water, nutrients, and pollutants accumulate on the enormous inner surface of the zeolite pores – and are released again when needed. One gram of zeolite can have an internal surface area of several square meters. This is why zeolite is so effective as a nutrient buffer, water reservoir, and natural filter – and fundamentally differs from a simple sponge, which absorbs rather than adsorbs.

Activation (tribomechanical ~) In the tribomechanical activation process, zeolite is altered at a molecular level through mechanical friction. This creates new, reactive surfaces – significantly increasing the mineral's adsorption capacity. Activated zeolite works faster and more intensely than untreated material. BODENKRAFT PUR uses tribomechanically activated zeolite to achieve maximum effect in the soil.

Aluminosilicate
Chemically, zeolite belongs to the group of aluminosilicates. This means that its crystal lattice consists essentially of silicon, aluminum, and oxygen. These building blocks are connected in a very ordered spatial structure, forming a stable mineral framework with many fine cavities and channels. This particular structure is precisely what makes zeolite so interesting.

The aluminum in the framework ensures that the structure does not remain electrically neutral. This allows certain positively charged particles, i.e., cations like sodium, potassium, calcium, or ammonium, to be bound in the zeolite and exchanged again. This ability is one of the most important foundations for zeolite's special effect in soil, stables, water, or technical applications. Simply put: zeolite is not just some stone powder, but a finely structured natural aluminosilicate with an astonishingly active internal order.

Ammonium (NH₄⁺)
Ammonium is a nitrogen-containing compound that is an important nutrient source for plants in the soil. Zeolite has a particularly high affinity for ammonium – it binds it to its negatively charged structures and releases it again in a controlled manner. This prevents nitrogen from being leached out during heavy rain or intense watering and makes the plant's nutrient supply more even and efficient.

B

Basalt meal
Basalt meal is produced by finely grinding basalt rock – a volcanic igneous rock rich in trace elements such as iron, manganese, zinc, and magnesium. Used in the garden, it improves soil structure, supplies plants with minerals, and promotes soil life. Basalt meal works slowly and sustainably – it is not a fast fertilizer but a long-term mineral basic supply for the soil.

Soil amendment
A soil amendment is a product that does not primarily provide nutrients but improves the properties of the soil itself – i.e., structure, water retention, aeration, or soil life. Zeolite is a classic soil amendment: it does not bring direct nutrients to the soil but improves its ability to retain nutrients, store water, and provide habitat for microorganisms. Leonardite, basalt meal, and compost are also considered soil amendments depending on their use. The term is legally relevant – in the EU, soil amendments are subject to different approval rules than fertilizers.

Fertilizer
A fertilizer supplies plants with directly available nutrients – nitrogen, phosphorus, potassium, and others. It aims to promote plant growth by providing nutrients. Fertilizers often work quickly and precisely but can damage soil life, leach nutrients into groundwater, and degrade soil structure in the long term if overused. Zeolite is explicitly not a fertilizer – it does not supply nutrients but improves the availability of existing nutrients. This distinction is important: zeolite does not replace fertilizer but makes it more efficient.

Soil tilth
Soil tilth describes the ideal condition of a soil: loose, crumbly, well-aerated, rich in humus, and teeming with microorganisms. A friable soil is easy to work, stores water optimally, and offers plants ideal growing conditions. Zeolite, compost, and active microorganisms work together to improve and maintain soil tilth in the long term.

Soil life
Soil life refers to the totality of all living organisms in the soil – bacteria, fungi, earthworms, mites, springtails, and many more. Active soil life is the basis for a fertile garden: it breaks down organic matter, makes nutrients available, improves soil structure, and protects plants from diseases. Zeolite supports soil life by providing habitat in its pores and creating favorable moisture conditions.

Soil structure
Soil structure describes how mineral particles, organic matter, water, and air are arranged in the soil. Good structure means stable aggregates (crumbs), sufficient air pores, and uniform water distribution. Poor soil structure – for example, due to compaction or humus loss – leads to waterlogging, drought stress, and poor root growth. Zeolite improves soil structure by creating stable micro-spaces between soil particles.

C

Clinoptilolite
Clinoptilolite is the most common and best-researched natural zeolite type. It belongs to the heulandite group of zeolites and is characterized by a particularly stable crystal structure and high cation exchange capacity. Clinoptilolite is the active ingredient behind most zeolite products for gardening, agriculture, and cosmetics. 

D

Drainage
Drainage refers to the ability of soil to drain excess water and prevent waterlogging. Good drainage is important for root respiration – roots need oxygen and cannot tolerate permanently waterlogged conditions. Zeolite granules improve drainage by creating voids in the soil through which water can drain without completely inhibiting water storage.

G

Rock flours
Rock flours are finely ground natural rocks, such as basalt, diabase, granite, or zeolite. They naturally contain many minerals and trace elements.

In gardening and agriculture, rock flours are valued because they can enrich soils with minerals in a gentle way. They do not work quickly like a fertilizer but slowly, balancing, and sustainably. Depending on the type of rock, they can improve soil structure, support soil life, and enhance compost.

Not all rock flours are the same. The decisive factors are the parent rock, fineness, purity, and origin. Zeolite rock flour plays a special role among rock flours because its porous structure allows it to additionally bind water, nutrients, and certain substances.

In short: Rock flours are natural mineral carriers made from finely ground rock that can sustainably support soils and natural cycles.

Granules 
Granules refer to zeolite in a coarse, granular form – in contrast to fine powder. Granules are particularly suitable for improving soil structure and aeration, as a drainage layer in pots and raised beds, and as a long-term water reservoir in deeper soil layers. BODENKRAFT PUR is available in both forms: as a fine powder for even distribution in the substrate and as granules for structure and aeration.

H

Hecht, Prof. Dr. Karl
Prof. Dr. med. habil. Karl Hecht was a German physiologist, sleep and stress researcher, and professor at the Charité in Berlin. Born in 1924, he shaped research on chronobiology, neurophysiology, and environmental medicine for many decades. In later years, he intensively studied natural minerals such as clinoptilolite zeolite and significantly contributed to zeolite being perceived in German-speaking countries not only as a technical mineral but also as a biologically and ecologically interesting natural material. He published numerous scientific papers and several books, including a highly acclaimed work on zeolite.

For many people, Karl Hecht is so significant because he tried to build bridges: between classical science, naturopathy, prevention, and a deeper understanding of natural regulatory processes. He described zeolite not as a miracle cure, but as a special mineral whose properties should be seriously researched and carefully classified. His name therefore still appears repeatedly today when it comes to clinoptilolite, soil detoxification, regulation, and natural approaches in agriculture. In the zeolite world, he is considered by many to be one of the most important pioneers of a well-founded, scientific engagement with this mineral.

Humic acids
Humic acids are complex organic compounds formed during the decomposition of organic matter. They are a main component of humus and play a central role in soil life: they improve soil structure, enhance water retention capacity, make nutrients more accessible to plants, and support root growth. Leonardite is a naturally occurring substance particularly rich in humic acids and is therefore used as a soil improver.

Humus
Humus is the organic matter in the soil that results from the decomposition of plant and animal materials. It is the heart of fertile soil: it stores water and nutrients, promotes soil life, improves structure, and makes the soil more resilient to heat and drought. Humus building is a slow process – zeolite and leonardite can effectively support and accelerate it.

I

Ion exchange
Ion exchange is the central mechanism of action of zeolite. The mineral's crystal structure carries a negative charge and attracts positively charged ions (cations) such as potassium, calcium, magnesium, or ammonium. These ions are stored and can later be released again when the plant needs them. This controlled exchange makes zeolite a natural nutrient buffer in the soil.

K

Cation Exchange Capacity (CEC)
Cation exchange capacity is a measure of how many positively charged nutrient ions (cations) a soil or mineral can store. The higher the CEC, the more nutrients can be bound and held available for plants. Zeolite has an exceptionally high CEC – significantly higher than most natural soils. This is one of the main reasons why zeolite is so effective as a soil additive.

Clinoptilolite → See Clinoptilolite (alternative spelling of the same zeolite type)

Granulation
Granulation describes the particle size of a material – from fine powder to coarse granules. For zeolite, granulation has a direct impact on its effect: fine powder has a larger surface area and acts faster; coarse granules improve soil structure and have a longer-lasting effect. For potting soil, fine powder is particularly suitable, while for raised beds or garden soil, granules are the better choice – or a combination of both.

Crystal structure
The crystal structure describes the internal arrangement of a mineral. In zeolite, this structure is particularly fascinating, as its framework consists of regularly arranged building blocks that together form a system of fine channels, cavities, and cage structures. This internal order is no accident but the basis for almost everything that characterizes zeolite.

In clinoptilolite, one of the most important natural forms of zeolite, several intersecting channels of precisely defined sizes run within the crystal. This allows water, ions, and small molecules to be taken up, stored, and released again. The crystal structure thus explains why zeolite can store water, exchange cations, and selectively bind certain substances. In short: the special effect of zeolite does not begin externally, but deep within its finely ordered internal architecture.

L

Leonardite
Leonardite is a naturally occurring weathering product of lignite that is extremely rich in humic acids. It is used as a soil improver to increase humus content, improve nutrient availability, and promote soil life. Leonardite works particularly well on leached, humus-poor soils – and ideally complements zeolite: while zeolite acts as a rapid buffer, leonardite builds up the humus structure in the long term.

M

Micron
A micron (µm) is one millionth of a meter – roughly the diameter of a human hair strand is 50–100 µm. The smaller the micron value of the zeolite powder, the finer the material and the larger the surface area where adsorption and absorption can take place. The more effective and efficient.

Microorganisms
Microorganisms are microscopic living beings – bacteria, fungi, yeasts, and others – that play a crucial role in the soil. They decompose organic matter, make nutrients available to plants, form symbioses with roots, and protect plants from pathogens. A healthy soil microbiome is the basis for a productive garden. AM PLUS contains active microorganisms that specifically build and strengthen soil life.

Micronization
Micronization refers to the extremely fine grinding of a material at the micrometer level. Micronized zeolite has an enormously increased surface area and thus significantly higher reactivity. It distributes more evenly in the soil or substrate and unfolds its adsorptive effect faster. For certain applications – such as in seed starting soil or as a feed additive – micronized zeolite is particularly suitable.

Mycorrhiza
Mycorrhiza refers to a symbiosis between fungi and plant roots. The fungus provides the plant with water and nutrients from the soil that it could not reach on its own – in return, the plant supplies the fungus with sugar. This symbiosis is widespread in healthy soils and is enormously important for plant growth. Zeolite, with its porous structure, creates ideal living conditions for mycorrhizal fungi in the soil.

P

Paramagnetism
Paramagnetism describes the weak magnetic attraction of certain materials in an external magnetic field. In connection with soils and minerals – including certain zeolite types and basalt rocks – paramagnetic properties are attributed a positive effect on plant growth. Research on this is still ongoing, but in organic agriculture, paramagnetism is increasingly being discussed as a quality feature for soil minerals.

pH value
The pH value indicates the acidity or alkalinity of the soil – on a scale from 0 (extremely acidic) to 14 (extremely alkaline). Most garden plants thrive best at a pH value between 6.0 and 7.0. Soil that is too acidic blocks nutrients, as does soil that is too alkaline. Zeolite acts as a natural pH buffer: it stabilizes the pH value and buffers fluctuations. For highly acidic soil, a combination of zeolite and GRÜNKRAFT CALCIUM is recommended.

Porosity
Porosity describes the proportion of voids (pores) in a material or soil. High porosity means plenty of space for water, air, and microorganisms. Zeolite is one of the most porous naturally occurring minerals – its internal surface area can be many square meters per gram of material. This extraordinary porosity is the reason for its high adsorption capacity and water storage capacity.

Powder
Zeolite in powder form has a very fine granulation and thus a very large surface area relative to its volume. It distributes evenly in the soil or substrate, works quickly, and comes into direct contact with fine roots and soil particles. BODENKRAFT PUR powder is ideal for seed starting soil, as an additive to compost, or for surface incorporation into existing beds.

S

Selectivity
Selectivity means that zeolite does not bind everything indiscriminately, but prefers to absorb certain substances over others. One can imagine this as a natural preference: depending on their structure, charge, and size, some ions or molecules fit better into the interior of the zeolite than others. This targeted selection is precisely what makes zeolite so special.

Selectivity primarily depends on the crystal structure, pore size, silicon-aluminum ratio, and the cations already present in the mineral. This is why a zeolite can, for example, be particularly receptive to certain ions, while others are only sparsely bound. For practical purposes, this is important because it means zeolite does not simply "absorb anything," but reacts very specifically in many applications — for example, with ammonium, odors, or certain pollutants.

Silicate
Silicates are minerals based on silicon dioxide (SiO₂) – and zeolite belongs to the large family of silicates. Silicates are the most common minerals in the Earth's crust and form the basis of most rocks. The special crystal structure of zeolite silicates – with their regular cavities and channels – is the key to all its useful properties as an adsorbent and ion exchanger.

Silicon (Si)
Silicon is the second most abundant element in the Earth's crust and an important trace element for plants and animals – although it was long considered non-essential. For plants, silicon strengthens cell walls, making them more resistant to fungal diseases, pests, drought stress, and heavy metal contamination. Plants well supplied with silicon stand more upright, have more stable tissue, and are generally more robust.

In the soil, silicon exists almost exclusively in bound form – as a silicate mineral, thus also in zeolite. Whether and how much of it is bioavailable to plants largely depends on the pH value and soil activity. Active microorganisms can help make bound silicon accessible to plants.

For animals – especially horses, dogs, and livestock – silicon also plays a role: it supports the formation of connective tissue, bones, fur, hooves, and claws. Zeolite as a silicate mineral contains silicon in its natural form. The exact bioavailability for animals is still being researched – but it is clear that silicate-rich minerals have been used intuitively in animal husbandry for centuries.

Trace elements
Trace elements are minerals that plants need only in small quantities – but without which nothing works. These include iron, manganese, zinc, copper, boron, and molybdenum. A deficiency of trace elements often manifests as discoloration, growth disorders, or poor yields. Zeolite and basalt meal contain natural trace elements and release them slowly into the soil – a gentle, natural supplement to the basic supply.

Synthetic zeolite vs. natural zeolite
Zeolite is not always the same as zeolite. A fundamental distinction is made between natural zeolite and synthetic zeolite. Natural zeolite is a naturally occurring volcanic mineral that formed over very long periods in the earth. It usually consists predominantly of clinoptilolite and also contains – depending on the deposit – other natural mineral components. Natural zeolite is particularly in demand for applications in gardening, agriculture, animal husbandry, or in the field of natural mineral products.

Synthetic zeolite, on the other hand, is artificially produced. It is created in the laboratory or in technical production processes and can be developed very specifically for certain properties. Such zeolites are mainly used in industry, for example in detergents, filters, catalysts, or technical drying systems. It is often important there that the structure is precisely defined and consistent.

The most important difference therefore lies in its origin: natural zeolite is a gift from the earth, synthetic zeolite is a specifically produced technical material. Both have a similar basic idea – namely a porous crystal structure with binding and exchange capabilities – but they are used for different purposes.

For many people, natural zeolite is particularly interesting because it is a naturally grown mineral with a complex composition. Synthetic zeolite, on the other hand, plays to its strengths where technical precision and uniform properties are required.

In short: Natural zeolite is the natural form of the mineral, synthetic zeolite is the industrially produced variant. Both have similar structures but different areas of application.

T

Tihomir Lelas
Tihomir Lelas is considered a prominent figure in connection with the tribomechanical grinding and activation of minerals. He developed processes in which natural minerals such as zeolite or limestone are not only very finely ground but also have their surface properties altered. His goal was to increase the natural reactivity of these substances so that they could fulfill certain binding, exchange, and surface processes even more effectively. With his developments and patents, his name became particularly well-known in the field of tribomechanically activated minerals.

In connection with zeolite, Tihomir Lelas is often mentioned because his work has shaped the idea that not only the chemical composition of a mineral is important, but also its physical processing. A zeolite is therefore not simply "ground" or "unground" – the way it is crushed and activated can also influence its surface, particle size, and reaction behavior. This is why Lelas' name is frequently encountered where tribomechanical activation, micronization, and particularly reactive forms of zeolite are discussed.

Tribomechanical grinding
Tribomechanical grinding is a high-energy grinding process in which zeolite crystals in a special mill repeatedly collide due to air currents and friction moving at hundreds of kilometers per hour. This breaks down the particles into their smallest components and simultaneously gives them additional "surface energy". The result: extremely fine powder particles with an enormously enlarged specific surface area, which can adsorb and absorb even more strongly than conventionally ground, virtually "crushed" zeolite. This process makes the zeolite "more vibrant" – it absorbs toxins, heavy metals, and moisture even more reliably and releases nutrients more specifically .

 

V

Vermiculite
Vermiculite is a naturally occurring mineral from the group of layer silicates. When heated strongly, it expands and becomes very light, loose, and porous. This is precisely why vermiculite is valued in many areas: it can store water, loosens substrates, and improves air circulation in the soil.
In horticulture, vermiculite is often used as an additive for seed starting soil, potting mixes, and potting soil. It helps to retain moisture longer without the soil becoming too heavy or too dense. This is particularly helpful when propagating plants, as young roots prefer consistent conditions.

However, vermiculite has a different strength compared to zeolite. While zeolite is primarily known for its binding capacity, cation exchange capacity, and selective absorption of certain substances, vermiculite is mainly used for its loose structure and water retention. Both minerals can improve substrates, but in different ways.

Volcanic mineral
Zeolite is a volcanic mineral – it forms when volcanic ash reacts with alkaline water and crystallizes over millennia. This geological history explains the mineral's unique structure: regular crystal lattices with uniform pores and channels, stable and long-lasting. In the soil, zeolite remains permanently and builds its effect over many years.

W

Water storage capacity
Water storage capacity describes how much water a soil or material can absorb and hold. It is one of the most important properties for productive garden soil – especially during heat and drought periods. Zeolite significantly increases the soil's water storage capacity: it absorbs water into its pores and releases it slowly as the soil dries out. Scientific studies show that soils with zeolite additives can retain up to 40% more water than untreated soils.

Z

Zeolite
Zeolite is a naturally occurring mineral with a unique, highly porous crystal structure. It can adsorb water, nutrients, and pollutants and release them in a controlled manner. These properties make it a versatile helper in gardening, agriculture, for animals, and for humans. There are over 40 natural zeolite types – the most important and best-researched is clinoptilolite. The geological origin of the zeolite is crucial for its quality – see the entries Zeolite of volcanic origin and Zeolite of sedimentary origin.

Zeolite of sedimentary origin Zeolite of sedimentary origin is considered the older, more mature, and higher-quality form of natural zeolite. It is formed by a very slow transformation of sedimentary rocks over millions of years under the influence of pressure, temperature, and mineral-rich water. This exceptionally long maturation period leads to a particularly stable, uniform crystal structure with high purity and reliably high cation exchange capacity. Its regulatory status is also crucial: zeolite of sedimentary origin is approved in the EU as a feed additive for all animal species – an important quality criterion that requires strict requirements for purity, composition, and effectiveness. Our zeolite products for animals are based on zeolite of sedimentary origin.

Zeolite of volcanic origin Zeolite of volcanic origin is formed when volcanic ash reacts with alkaline water and is transformed into a silicate crystal over millennia. Geologically, this process is significantly faster than the formation of zeolite of sedimentary origin – the mineral is therefore younger and its crystal structure is less mature. Zeolite of volcanic origin is well suited for many applications in gardening and agriculture. It is important to know: for use as a feed additive for animals, it is not approved for all animal species in the EU – here, sedimentary zeolite is the regulatory safe and recommended choice. Anyone using zeolite for their animals should therefore always pay attention to the origin and the corresponding approval.

Zeolite activation → See Activation (tribomechanical ~)

Zeolitization Zeolitization refers to the geological process in which volcanic rocks or ashes are converted into zeolite through chemical reactions with water. This process takes thousands to millions of years under natural conditions and explains why zeolite deposits are found worldwide primarily in volcanically active regions.

 

 

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This glossary is constantly being expanded. Is there a term missing? Write to us – we're happy to help.