No, air is not a mineral. It does not meet the qualifications to be considered a mineral, in that it is not a solid, and does not have a consistent and orderly structure.
Why Is Air A Mineral? (Or Not?)
What Does It Take To Be Considered A Mineral?
To be considered a mineral (chemically and scientifically, not legally or for the purpose of establishing mineral rights), a substance must meet five qualifications.
If the substance fails on any of the qualifications, it cannot be a mineral.
First, the substance must exist naturally. Humans can also make it, but it must exist without human involvement. (Diamonds are a good example)
Second, the substance must be a solid at normal Earth temperatures for the substance.
For example, hydrogen is generally a gas. But if you increase the pressure and drop the temperature on a sample, well beyond what we’d see here anywhere on the surface of the Earth, it can be forced into solid form.
But hydrogen is not considered a metal because the circumstances are so unnatural.
Third, the substance must be completely inorganic.
This doesn’t mean what it means in the fruit and veg section of the grocery store.
Instead, the substance must have no organic molecules, which are usually molecules with carbon to hydrogen bonds.
Fourth, the substance needs to have a consistent chemical composition, regardless of where you take the sample.
Fifth, the internal structure of the material must be orderly and consistent.
Some good examples of minerals are: gold, quartz, calcite, feldspar, olivine, mica, and fluorite.
Some good examples of materials that are not minerals are: basalt, granite, soil, and water,
Other Ways “Mineral” Is Used
This article focuses on the geological aspects of whether a substance is considered a mineral.
But other experts use the term “mineral.”
A nutritionist, for example, calls inorganic substances that organisms need to carry out body processes a mineral, or mineral nutrient. These include copper, sulfur, magnesium, and more.
It should be noted that many of these substances would also pass the test to be considered a geological mineral, but not necessarily all.
People also use mineral to describe commodities or materials, especially those that have value and can be sold (like oil, gas, or crushed rocks), even though these materials do not meet the geological qualifications to be a mineral.
What is Air?
In general, at normal Earth temperatures, air is a gas (as opposed to a liquid or solid).
It is a mixture of several substances which are also gases, such as oxygen, argon, neon, helium, carbon dioxide, and more.
Air also usually contains some evaporated water molecules, as well as pollution particulate matter.
Does Air Pass The Mineral Qualifications?
It is pretty obvious from the get-go that air fails to meet the qualifications, primarily because air is a gas and not a solid.
Secondary to that is the fact that while the composition of gases in air is consistent, the impurities/pollutants/water in the air varies dramatically from place to place.
In fact, it might be better to call air a scientific mixture, because it is made up of multiple substances that are not bonded to each other.
Next, as it is in a gaseous form, the molecules in the substance are moving. Consequently, there is not an orderly or consistent structure to the substance.
On the upside, air exists in nature without the assistance of humans, but that does little in the end.
Is Air A Mineral In Terms Of Being A Commercial Commodity Mineral?
This is a really interesting question.
Clean air is something of value that people may in the future seek to buy and sell.
Or perhaps the quality of the air will influence the value of the property (cleaner air means higher demand and thus a higher price). (source)
But for now, air is not yet treated in the same way that we treat gas and oil rights on land.
To sum, because air is not a solid, and it’s structure is inconsistent and disorderly, air is not considered a mineral.