Issue #415 What's The Number on That Mineral Water Mean?

Walk down the bottled-water aisle and most labels greet you with a place, a family name, or a poetic nod to nature. Then, every so often, you meet a bottle called something like “No. 4” or “No. 17.” It can feel a little mysterious. Is the number a mineral score? A recipe? The year the water was discovered? Did Waters No. 1 through No. 3 fail the taste test? Usually, the answer is much more practical and far more interesting. A number on a mineral-water label may identify a particular spring, well, borehole, source, or officially recognized mineral-water type. In other words, it often comes from the water’s scientific or geographic record rather than a modern branding meeting.

A Number Can Be an Address

Mineral-water regions can contain several springs and wells within the same general area. Although these sources may be geographically close, their waters are not necessarily identical. Water moving underground encounters different rock layers, temperatures, pressures, gases, and travel times. One source might produce relatively light calcium-rich water, while another nearby source delivers something considerably saltier, more carbonated, or richer in bicarbonate. Hydrogeologists need a reliable way to distinguish them, so individual springs and wells are often numbered during exploration and classification.

Think of the number as an underground address. Historically, that number might have referred to the original spring. Later, as bottling operations developed and deeper wells were drilled, the familiar number could become associated with a recognized water type. That type is defined not merely by a single opening in the ground, but by its place of origin and expected mineral characteristics. This distinction matters. A number on the front of the bottle does not always match the number of the modern well currently supplying it. You may find additional well numbers printed elsewhere on the label, in a water-quality report, or in official source documentation.

The Story of No. 4 and No. 17

Essentuki No. 4 and Essentuki No. 17 are excellent examples. Both names come from the Essentuki mineral-water field in Russia’s Caucasian Mineral Waters region. In 1823, physician and researcher Alexander Nelyubin studied and classified numerous springs in the area. Springs No. 4 and No. 17 became especially valued, and their identification numbers eventually became the names by which the waters were known.

Today, “Essentuki No. 4” and “Essentuki No. 17” refer to recognized mineral-water types with defined origins and chemical profiles. Scientific research describes the Essentuki basin as containing waters with a wide range of mineralization, pH levels, dissolved gases, and chemical compositions. No. 4 and No. 17 belong to the region’s characteristic carbon-dioxide-rich, bicarbonate-chloride waters. Research confirms that the differences underground are real—not simply matters of packaging. The important lesson is that 17 is not “better” than 4, and it does not mean the water contains 17 minerals. These are identifiers with historical roots. Still, the two numbers lead us to distinctly different experiences in the glass.

When Concentration Changes the Water’s Personality

Essentuki No. 4 is the more moderately mineralized of the pair, generally falling around 7–10 grams of dissolved minerals per liter. No. 17 is more highly mineralized, commonly around 10–14 grams per liter. Exact figures can vary within the limits established for each recognized type, so the bottle’s current analysis is always the best reference.

That difference in mineral concentration changes four major parts of the tasting experience: body, salinity, finish, and occasion.

Body: Highly mineralized water can feel fuller and more substantial across the palate. Instead of disappearing quickly, it may seem almost weighty. No. 4 has a firm mineral presence, while No. 17 generally presents an even denser, more commanding texture.

Salinity: Sodium and chloride can produce a noticeably salty or savory character. In a strongly mineralized water, that quality may remind you of salted crackers, broth, or even a faint breeze from the sea. No. 17 usually expresses this salinity more forcefully than No. 4.

Finish: Low-mineral water often leaves a short, clean finish. Mineral-rich water can linger. Bicarbonate, sodium, chloride, natural carbon dioxide, and other components may leave alkaline, saline, tangy, or slightly bitter impressions after the sip.

Drinking occasion: A delicate water can work beautifully as an easy, everyday thirst quencher. A highly mineralized water asks for more attention. It may be served in a smaller portion, tasted slowly, or examined alongside food as part of a mineral-water flight. Traditionally, some highly mineralized waters have also been consumed within spa and medical traditions. That history is fascinating, but it should not be treated as universal medical advice. Anyone using mineral water for a health condition—especially someone limiting sodium—should consult a qualified healthcare professional.

Read Beyond the Number

A numbered name is the beginning of the investigation, not the complete water report. Turn the bottle around and look for:

• The named source or extraction location

• The specific spring, borehole, or well number

• Total dissolved solids or total mineralization

• Major minerals such as calcium, magnesium, sodium, bicarbonate, sulfate, and chloride

• Whether the carbonation is naturally present, reinforced, or added

• Any classification such as natural mineral water, table water, or therapeutic mineral water

Numbers can preserve a surprising amount of history. They connect today’s bottle to early field surveys, spa culture, geological research, and the careful work of distinguishing one underground water from another. So, the next time a mineral water introduces itself with a number, do not think of it as a ranking. Think of it as a clue a small piece of a much larger story written beneath the ground.