Several terms that are commonly used in conversations about silver are briefly described below. The terms appear in alphabetical order.
Acid: On a pH scale, an acid describes the condition of materials with a pH measurement of under 7. Acidic substances react with bases.
Alkaline: On a pH scale, alkaline is another word for basic (“bases and acids”) that describes the condition of materials with a pH measurement of over 7. Alkaline substances react with acids. Human blood is a mild alkaline substance that typically ranges between 7.35 and 7.45.
Argyria: A condition where areas of the skin and other body tissues turn to a grey or blue-grey color. Silver that comes out of suspension and settling into fats can cause argyria; this is also possible with silver salts, silver proteins, and other silver products of dubious origin.
Colloid: A colloid is a particle between 1 and 1000 nanometers in diameter that is evenly dispersed throughout another substance. Examples of colloidal substances include whipped cream, styrofoam, fog, milk, smoke, and blood. A colloidal system may be liquid, solid, or gaseous.
Colloidal Silver : Colloidal silver is a system with small particles (colloids) of silver evenly dispersed in a liquid, typically water. Colloidal silver has been produced in a wide variety of forms for over 100 years, with variations in concentration, purity, stability, colloid size, molecular structure, etc. These variations result in vastly different substances that are commonly referred to under the general term “colloidal silver.”
Hydrocolloid: Hydrocolloids can be a foam, emulsion, or sol, depending on whether the colloid dispersed within water is a gas, liquid, or solid. It is essentially a colloidal system where the colloid is evenly dispersed within water.
Ion: An ion is an atom or molecule with an unequal number of electrons and protons. As a result, an ion has a net positive or negative charge. If the ion has a negative charge (it has more electrons than protons), it is called an anion. If the ion has a positive charge (it has fewer electrons than protons), it is called a cation.
Ionic Silver: Ionic silver is the state of silver in an ionic form, and is commonly found within creams and liquids. Prior to the advent of digital photography, ionic silver was widely used as one of the chemicals employed to process film.
Nano Silver: A colloquial term used to describe the presence small particles of silver within another substance. Examples include a silver powder applied to a surface, silver fibers within a matrix or mesh fabric, or silver particles within water. The size of these particles is presumed to be very small (so small that the use of nanometers is required), but there is no definitive range of size connected to this term. Alternately, and much more commonly in everyday speech, “nano silver” refers to a small iPod with a metallic finish.
Nanometer: A tiny unit of length, a nanometer (also spelled “nanometre”) is 1 billionth of a meter, or 1×10-9m, and is denoted by the symbol “nm”. There are ten angstroms in one nanometer. The term “nanotechnology” is related in the sense that it refers to “very small technology”, technology in which pertinent sizes can be measured in nanometers. A nanometer, however, is strictly a unit of measurement, not unlike a centimeter (cm), kilometer (km), or millimeter (mm).
Parts Per Million: Parts per million (ppm) is a common notation for describing the amount of a dissolved mineral within water. It is measured by the mass of dissolved material in comparison to the mass of the water. As an example, if time were measured in ppm, 10 ppm would translate into about 5 or 6 minutes within a year.
pH: Based on the activity of hydrogen ions, pH is a measure of acidity of alkalinity of a given substance. The “p” in pH has been defined in multiple ways, including “potential,” “power,” and many others. On a pH scale, 0 is very acidic, while 14 would be very basic. 7 is considered neutral.
Silver Nitrate: Considered a salt of silver, silver nitrate is an inexpensive product. Its structure allows it to dissolve into many solvents, including water.
Silver Protein: The combination of silver and a protein binder is known as “silver protein”. Silver proteins can cause argyria.
Silver Salts: Silver salts are compounds that combine silver with one or several of a large range of additional elements. Many silver salts can be toxic, although silver itself is not. Silver salts can cause argyria.
Silver Solution: Silver solution is a broad term, and can connote many different types of solutions containing silver. When trying to distinguish silver solutions from one another, precise terms are very helpful. Variations in the solute and the solvent can greatly affect the character of the solution. “Silver solution”, as commonly used, typically refers to water mixed with tiny amounts of silver, but a “solution” can be a solid, liquid, or gas.
Sol: A sol is a colloidal system, a substance where tiny particles (1 to 1000 nanometers in diameter) of a given material are suspended within a liquid. If the liquid in a system is water, the sol might also be referred to as a hydrosol or aquasol. Older silver products marketed as silver hydrosol or silver aquasol are named so because they are a sol (silver) suspended in a liquid (water).