Types of Silver

As you’ve been exploring your options for silver, you’ve probably noticed that there are a multitude of colloidal silver products marketed with different claims about their attributes. This breadth of options in the colloidal silver market is testament to the known benefits of silver, but it can be confusing to understand the difference.

Many forms of silver exist, with physical and chemical differences leading to their identification, just like other elements on the periodic table. Similarly, there are many forms of chlorine: e.g., sodium chloride, as in table salt; muriatic acid, like you put in a swimming pool; or chlorofluorocarbons, which deplete the ozone layer. Most have different physical and chemical properties, giving them entirely different efficacy and toxicity profiles; the body metabolizes them differently and absorbs, distributes and eliminates them via different pathways or methods. Their uses and applications vary, as a result.


In this section, you will learn about the following:

‣ Comparison of types of silver on the marketplace

‣ Helpful facts to keep in mind when comparing types of silver

‣ What distinguishes Bio-Active Silver Hydrosol from the other types of silver

Some common forms of silver marketed as ingestible dietary supplements in the USA, as drugs or for topical applications include:

Comparison of
Types of Silver

Colloidal Silver (Dietary Supplement)

Definition: A suspension containing silver particles plus silver ions. When homemade, a typical do-it-yourself product without control of materials, Concentration or composition.

Example: Homemade Typical concentration: 1-20,000ppm

Toxicity: Depends upon the dosage of silver and impurities. Colloidal silvers often require larger dosages to achieve similar efficacy to other products, thereby increasing potential toxicity risks.

Particle Size: Variable Particle size (10-1000nm), average 8-12% charge

Remarks: A common form. Most silver is metallic and therefore inactive, getting excreted as waste without any health benefits.

True Colloidal Silver (Dietary Supplement)

Definition: A marketing term; implies completely suspended particles of inactive metallic silver and no bio-active ionic silver.

Example: Typical concentration: 3-200ppm

Toxicity: Depends upon the dosage of silver and impurities. Colloidal silvers often require larger dosages to achieve similar efficacy to other products, thereby increasing potential toxicity risks.

Particle Size: Variable Particle size (range 1-1000nm)

Remarks: Claim is based upon poor understanding of Surface Plasmon Resonance in silver nanoparticles. Silver nanoparticles have a range of optical properties (colors) from clear to yellow to orange to brown to blue to green to purple, depending upon their size, shape and concentration.

Ionic Silver (Dietary Supplement)

Definition: A solution containing silver ions with a charge (+1)

Example: Silver nitrate CASRN 7761-88-8 Typical concentration: 1,000-10,000ppm

Toxicity: Depends upon concentration and on exact composition. Milk, soy, and egg proteins when unlabeled can pose allergy risks

Particle Size: No particles unless from impurities

Remarks: Still used in medicine, i.e., to prevent blindness in newborns

Silver Protein (Drug)

Definition: Ionic or colloidal silver with a protein added for stability. Added proteins are typically egg albumin, casein from milk, or soy based.

Example: Mild Silver Protein (MSP) Typical concentration: 50-10,000ppm

Toxicity: Concentration-dependent; Toxicity rises with concentration. Toxicity also dependent upon the type of salt (e.g., silver nitrate is more toxic than silver chloride)

Particle Size: Variable Particle size (50-2000nm)

Remarks: Addition of protein may reduce bioactivity of silver significantly.

Silver Hydrosol (Dietary Supplement)

Definition: Pure mixture of positively charged silver ions and silver nanoclusters

Example: Sovereign Silver Typical concentration: 10 ppm

Toxicity: Extremely low

Particle Size: Particle size as small as 0.8 nm

Remarks: The ultimate refinement of the colloidal silver category, appropriately called silver hydrosol to distinguish it from other forms of colloidal silver.

Homeopathic Silver (Drug)

Definition: A specially made formulation containing immeasurably low amounts of silver, achieved by dilution and succession.

Example: Argentum Nitricum, Argentum Metallicum Typical concentration: practically immeasurable

Toxicity: None

Particle Size: N/A

Remarks: In the USA, the efficacy of Homeopathic Medicines is evaluated by the HPCUS. It is outside the scope of the FDA. Once efficacy is established, substances are listed by the HPUS and/or different Materia Medica, such as Clarke, Boericke, Kent.

Silver Compounds (Drugs)

Definition: A compound is a substance formed when two or more chemical elements are chemically bonded together. In a silver compound, one of the elements must be silver.

Example: Silver sulfadiazine

Toxicity: None

Particle Size: Variable Particle size (10-1000nm)

Remarks: Some are widely used in medicine still, including for the treatment of severe burns.

 *Above numbers and representations are general in nature.

Helpful Facts

⁃ Ionic silver may or may not contain particles (although particles of some kind are also ubiquitous).

⁃ Since ancient times, the silver ion has been known to be effective against a broad range of microorganisms.

⁃ Particles have been found to act as a reservoir for the further release of ions.

⁃ Suspended (particulate) silver is generally less stable than ionic silver (and will have a shorter shelf life). It has far less bioavailable silver.

⁃ A colloid is a substance which contains suspended microscopic particles.

⁃ Silver is a heavy metal, but it is not classified as a toxic heavy metal. However, all metals can be toxic, just as all elements may be toxic at certain levels – even water. As with anything that has a toxicity profile, one should take only the amount required to achieve a therapeutic effect. One would never take a 20-gram tablet of aspirin, so why would one take a 5,000 ppm silver product? In fact, with metals, the oligodynamic effect discovered in the late 1800s showed that certain metals exerted much greater activity at extremely low concentrations than at higher concentrations.

What Distinguishes
Bio-Active Silver Hydrosol
from the Rest?

Colloidal silver is the generic term for all forms of silver marketed as dietary supplements and containing substances that include particles in suspension.

Homemade colloidal silver is often made from silver generators that produce low quality, poorly defined homemade colloidal silver, of mostly unknown purity, concentration, particle size and particle charge. The lack of control over what is produced creates a greater potential for causing argyric reactions and increasing the toxicity risks. (It would be unrealistic for one to make their own acetaminophen in a homemade chemistry kit and expect brand-name quality and efficacy.)

Bio-Active Silver Hydrosol is a mixture of silver ions and silver nanoclusters as small as 0.8nm in size. It is not to be confused with “ionic silver” which means, by definition, that the product should be comprised entirely of silver ions. Silver Hydrosol is composed of only 2 ingredients: 99.999% pure silver and USP 23, the FDA monograph for pharmaceutical grade purified water. It represents a unique blend of the most active and effective species of silver (positively charged silver ions and the smallest type of silver nanoparticles called nanoclusters) at such low concentration as to present no fear of toxicity. A Bio-Active Silver Hydrosol has the smallest particles and highest charge ratio of any colloidal silver product, and so represents the ultimate refinement of the colloidal silver category.

Silver Hydrosol is not “true colloidal silver” either, as the term “true colloidal silver” is a marketing term with no basis in science to distinguish it from other colloidal silver products, meaning the solution should be 100% particulates. Scientifically, 100% particulate silver would be unstable without proteins or chemicals to stabilize them. Furthermore, large particles cannot be converted into the bioactive form on the timescale of interaction with the body, rendering the vast majority of the silver wasted.

Ionic silver is a solution of silver that does not necessarily contain silver particulates. Recent literature has illustrated the fact that silver particles and silver ions exist in a complex equilibrium cycle, which can be altered based on the presence of light, proteins, starches, natural molecules and synthetic molecules. These changes can significantly reduce the amount of available silver ions.

Silver protein is a silver compound, and it includes ingredients that compromise purity (addition of a casein or protein of vegetal or animal origin to keep the silver in solution). In the USA, silver proteins are considered drugs by the FDA. 

There are other forms of silver besides those mentioned above, but by using any of them one would be trading increased toxicity for reduced efficacy, and so there is little reason to expound further upon them.

Silver 101

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Silver 101

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The Silver Marketplace

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History of Silver

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Types of Silver

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Benefits of Silver

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Safety & Toxicity

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Choosing the Right Silver

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Making Your Own Silver

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Myths About Silver

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