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 that 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 seemingly disappears inside and is bound there. A classic example is a sponge soaking up water: The water is inside, but no longer freely available on the surface. In soil, absorption refers, for example, to 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, on the other hand, refers to the accumulation of substances on a surface – not inside a material, but on its outer or pore walls. The adsorbed substances adhere to the surface but can also be detached and specifically released again under changed 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 inner surface 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 instead of adsorbs.

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

Aluminosilicate
Zeolite chemically belongs to the group of aluminosilicates. This means that its crystal framework essentially consists of silicon, aluminum, and oxygen. These building blocks are connected in a very ordered spatial structure and form a stable mineral framework with many fine voids and channels. It is precisely this special structure that 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 such as sodium, potassium, calcium, or ammonium, to be bound and exchanged again in the zeolite. This ability is one of the most important foundations for the special effect of zeolite in soil, stables, water, or technical applications. Simply put: Zeolite is not just any rock powder, but a finely structured natural aluminosilicate with an astonishingly active internal order

Ammonium (NH₄⁺)
Ammonium is a nitrogen-containing compound that is considered 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 washed out during heavy rain or intensive watering and makes the nutrient supply to the plant 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 quick fertilizer, but a long-term mineral basic supply for the soil.

Soil amendment
A soil amendment is a product that does not primarily supply nutrients, but rather improves the properties of the soil itself – i.e., structure, water storage, aeration, or soil life. Zeolite is a classic soil amendment: It does not provide direct nutrients to the soil but improves its ability to hold nutrients, store water, and provide habitat for microorganisms. Leonardite, basalt meal, and compost also count as 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 / Fertilizers
A fertilizer provides plants with directly usable nutrients – nitrogen, phosphorus, potassium, and others. It is intended to promote plant growth by supplying nutrients. Fertilizers often act quickly and targeted, but if overused, they can harm soil life, leach nutrients into groundwater, and worsen soil structure in the long term. Zeolite is expressly not a fertilizer – it does not supply nutrients but improves the availability of already existing nutrients. This difference is important: Zeolite does not replace fertilizer but makes it more efficient.

Soil tilth
Soil tilth describes the ideal state of a soil: loose, crumbly, well-aerated, rich in humus, and enlivened by 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 even 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 microspaces 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 a soil to drain off 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 preventing 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 gently enrich soils with minerals. They do not act 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 every rock flour is the same. The starting rock, fineness, purity and origin are crucial. Zeolite rock flour plays a special role among rock flours because, due to its porous structure, it can also 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 over many decades. In later years, he intensively studied natural minerals such as clinoptilolite zeolite and made significant contributions to the perception of zeolite 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 regarded work on zeolite.

For many people, Karl Hecht is so significant because he tried to build bridges: between classical science, natural medicine, 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 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, scientifically oriented examination of this mineral.

Humic acids
Humic acids are complex organic compounds that are 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, promote water retention capacity, make nutrients more accessible to plants, and support root growth. Leonardite is a natural substance particularly rich in humic acids and is therefore used as a soil improver.

Humus
Humus is the organic matter in the soil that is formed by 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 resistant to heat and drought. The build-up of humus 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 crystal structure of the mineral 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 made available to 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)

Granulometry
Granulometry describes the particle size of a material – from fine powder to coarse granules. For zeolite, granulometry has a direct influence on the effect: Fine powder has a larger surface area and acts faster; coarse granules improve soil structure and have a longer-lasting effect. Fine powder is particularly suitable for potting soil, while granules are the better choice for raised beds or garden soil – 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, voids and cage structures. This internal order is no coincidence, but the basis for almost everything that distinguishes zeolite.

In clinoptilolite, one of the most important natural forms of zeolite, several intersecting channels of precisely defined sizes run through the crystal. This allows water, ions, and small molecules to be absorbed, 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 on the outside, but deep within its finely ordered inner architecture.

L

Leonardite
Leonardite is a naturally occurring weathering product of lignite, extremely rich in humic acids. It is used as a soil conditioner 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 fast buffer, leonardite builds up the humus structure long-term.

M

Micron
A micron (µm) is one millionth of a meter – the diameter of a human hair strand is about 50–100 µm. The smaller the micron value of the zeolite powder, the finer the material and the larger the surface area available for adsorption and absorption. This makes it more effective and powerful.

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. The product AM+PLUS contains active microorganisms that specifically build and strengthen soil life.

Micronization
Micronization refers to the extremely fine grinding of a material to a micrometer level. Micronized zeolite has an enormously enlarged surface area and thus a significantly higher reactivity. The powder distributes more evenly in the soil or substrate and develops its adsorptive effect faster. For certain applications – such as in propagation soil or as a feed additive – micronized zeolite powder 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 alone – in return, the plant supplies the fungus with sugar. This symbiosis is widespread in healthy soils and 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 the context of soils and minerals – including certain types of zeolite and basalt rocks – paramagnetic properties are attributed a positive effect on plant growth. Research on this is still ongoing, but in organic farming, 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 available – 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 grain size and thus a very large surface area relative to its volume. It distributes evenly in the soil or substrate, acts quickly, and comes into direct contact with fine roots and soil particles. BODENKRAFT PUR Powder is ideal for propagation soil, as an additive to compost, or for surface incorporation into existing beds.

S

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

Selectivity primarily depends on the crystal structure, pore size, silicon-aluminum ratio, and the existing cations in the mineral. Therefore, a zeolite, for example, can be particularly receptive to certain ions, while others are only minimally bound. This is important for practical applications because it means zeolite doesn't just "soak up anything," but reacts very specifically in many applications — for instance, 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 intuitively used 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 slowly release them into the soil – a gentle, natural supplement to basic supply.

Synthetic Zeolite vs. Natural Zeolite
Zeolite is not always the same as zeolite. A distinction is generally made between natural zeolite and synthetic zeolite. Natural zeolite is a naturally occurring volcanic mineral, formed over very long periods in the Earth. It consists mostly of clinoptilolite and, depending on the deposit, also contains other natural mineral components. Natural zeolite is particularly sought after 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 through technical production processes and can be specifically developed for certain properties. Such zeolites are primarily used in industry, for example, in detergents, filters, catalysts, or technical drying systems. In these applications, it is often important that the structure is precisely defined and consistent.

The most important difference lies in their origin: natural zeolite is a gift from the Earth, while synthetic zeolite is a deliberately produced technical material. Both share 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, excels 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 formative 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 altered in their surface properties. His goal was to increase the natural reactivity of these substances so that they could perform 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 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 reactive behavior. Therefore, Lelas's name is often encountered where tribomechanical activation, micronization, and particularly reactive forms of zeolite are discussed.

Tribomechanical Grinding - Pulverization
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 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, quasi "crushed" zeolite. This process makes the zeolite "more alive" – it absorbs toxins, heavy metals, and moisture even more reliably and releases nutrients more selectively. 

 

V

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

Compared to zeolite, however, vermiculite has a different strength. 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 unique structure of the mineral: regular crystal lattices with uniform pores and channels, stable and long-lasting. In the soil, zeolite remains permanently effective 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 retain. 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 slowly releases it as the soil dries out. Scientific studies show that soils with added zeolite 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 aid 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 characteristic that requires strict requirements for purity, composition, and efficacy. 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 speaking, this process is significantly faster than the formation of zeolite of sedimentary origin – the mineral is therefore younger and the crystal structure is less mature. Zeolite of volcanic origin is well suited for many applications in gardening and agriculture. Important to know: For use as a feed additive in animals, it is not approved for all animal species in the EU – here, sedimentary zeolite is the regulatively 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, mainly in volcanically active regions.

 

 

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