Many people assume that the “jewels” inside a watch are decorative gemstones, perhaps like the diamonds set into a luxury bezel. This is a common and understandable misconception. In reality, watch jewels have absolutely nothing to do with fashion and everything to do with fundamental engineering. They are not sparkling decorations; they are tiny synthetic rubies or sapphires used as high-performance bearings inside the movement, components that are absolutely critical for keeping your watch running smoothly, accurately, and reliably for decades.
If you’ve ever seen the markings “17 jewels” or “21 jewels” printed on a watch dial or engraved on a movement plate and wondered what these numbers truly signify, this guide provides the comprehensive explanation.
What Exactly Are Watch Jewels?
In simple terms, watch jewels are small, precisely manufactured components that serve one crucial purpose: friction reduction.
A mechanical watch movement is a vast network of finely tuned metal components: gears, pinions, levers, and wheels that are constantly moving, rotating, and interacting. When metal parts repeatedly move against one another, even under minimal pressure, the friction generated is significant. This friction creates two major problems: premature wear on the components and a loss of accuracy in timekeeping.
To solve this, watchmakers place these ultra-hard, smooth synthetic stones at the key contact points. The pivots of the gears rest inside the jeweled bearings, allowing the metal parts to glide with minimal resistance. The jewels don’t add beauty; they add precision and remarkable longevity to the mechanism.
What Are They Made Of?
The choice of material is purely scientific and based on one factor: hardness.
Modern watch jewels are lab-grown sapphires or rubies. Chemically, both are forms of corundum. Crucially, both materials rank a 9 on the Mohs hardness scale, placing them just below diamond (10). This extreme hardness allows the jewels to:
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Resist Scratches and Abrasion: They are virtually unaffected by the metal pivots rotating against them over decades of use.
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Maintain Consistency: Their polished, ultra-smooth surface remains consistent, ensuring the low-friction performance doesn't degrade over the watch's lifetime.
While early watchmakers in the 18th century used natural rubies and diamonds, the development of synthetic production in the 20th century made jeweled movements affordable, consistent, and standard across all levels of mechanical watch brands.
Why Are Jewels Used in Watch Movements?
A mechanical watch is a network of finely tuned gears, pinions, and wheels that move continuously. Jewels are placed at friction-heavy points like pivots and escapements to minimize resistance. This leads to smoother motion, better timekeeping, and longer service intervals.
Without jewels, the constant contact of metal parts would lead to micro-abrasions, causing a loss in accuracy and faster degradation of the movement.
Typical areas where jewels are found include:
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Gear train pivot bearings: For the center, third, and fourth wheels.
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Balance wheel pivots: Often protected by shock-absorbing cap jewels.
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Pallet fork pivots and pallet jewels: Critical parts of the escapement.
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Escape wheel pivots.
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Automatic winding modules and Calendar mechanisms: In more complex watches.
If your watch has a display back, you may even spot these small pink or red dots shining within the movement that is the visible evidence of this critical engineering.
A Brief History of Watch Jewels
The concept of using jewels in watches dates back to the early 1700s when Nicolas Fatio de Duillier and the Debaufre brothers first introduced the idea. They discovered that natural rubies reduced friction far better than metal. For centuries, this technique was reserved for high-end Swiss watches since natural gemstones were expensive.
By the 1900s, the development of synthetic rubies made jeweled movements accessible to all. It became a standard, expected feature in both affordable and luxury mechanical watches, ensuring better durability and consistency across the industry.
The Meaning Behind the Number: 17, 21, and Beyond
The number of jewels listed on a watch indicates the total count of functional jewel bearings within the movement. This count is a direct reflection of the movement’s design complexity.
What Does “17 Jewels” Mean?
When you see “17 jewels” engraved on a watch movement, it means the movement contains 17 functional jewel bearings. These are placed at all critical pivot points required for smooth gear operation.
A 17-jewel watch is considered fully jeweled, meaning every key component in a simple hand-wound or automatic movement has jewel support. This configuration includes bearings for the center wheel, third wheel, fourth wheel, escape wheel, balance wheel, and pallet fork.
What About “21 Jewels”?
A 21-jewel movement includes a few extra jewels beyond the essential 17. These are often added in:
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The automatic winding mechanism, which requires low-friction bearings to operate efficiently.
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Extra cap jewels strategically placed to minimize positional errors (small timing variations that occur when the watch is tilted).
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Bearings supporting secondary mechanisms like the date or calendar function.
In essence, more jewels often mean a more mechanically complex watch with added functions, not necessarily a more accurate one.
Do More Jewels Mean a Better Watch?
Not always. While jewel count can indicate the number of components in a movement, more jewels don’t automatically translate to superior performance or value. A simple, well-regulated 17-jewel watch that is expertly serviced can be more reliable than a poorly designed 30-jewel one.
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Complexity: A chronograph (stopwatch function) or a perpetual calendar will inevitably have 30, 40, or even 50+ jewels because they contain many more complex systems that require functional jewel support.
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Marketing Counts: Some brands in the mid-20th century regrettably inflated jewel counts for marketing purposes, adding decorative or unnecessary jewels that served no functional role. In modern watchmaking, jewel count should be understood as a reflection of movement design, not a simple measure of luxury level.
Most high-quality mechanical watches contain between 17 and 25 jewels, depending on their core functionality. Extremely complicated pieces, such as the Patek Philippe’s Grandmaster Chime, may exceed 200 jewels, but this is a rare exception for ultra-complex grand complications.
The Different Roles Jewels Play
Watchmakers utilize several different types of jewels, each engineered for a specific function:
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Hole Jewels: These have a tiny hole bored through them to accommodate an axle or pivot. They serve as the primary, low-friction bearings for rotating gears.
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Cap Jewels: Flat jewels placed on top of hole jewels, typically used on the balance staff. They prevent vertical movement of the pivots and provide shock protection.
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Pallet Jewels: Small, often rectangular jewels fixed onto the pallet fork that interact directly with the escape wheel, controlling the crucial release of energy.
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Roller Jewels: A single jewel attached to the balance wheel that transfers impulses from the escapement to keep the wheel oscillating.
Together, these different jewel types help the movement run precisely and extend its life span by mitigating the destructive forces of friction and impact.
Final Thoughts: An Appreciation of Hidden Craftsmanship
Jewels in a watch are not for decoration; they are functional components that help the movement run efficiently, maintain accuracy, and extend the lifespan of the mechanism.
A 17-jewel watch is more than capable of providing precise, reliable performance. A 21-jewel or higher count usually signals added complexity, such as an automatic winding system or calendar functions.
Understanding what jewels do helps you appreciate the hidden engineering and craftsmanship behind mechanical timekeeping. Whether your watch has 17 or 37 jewels, each tiny ruby inside plays its part in keeping your timepiece alive, accurate, and ticking for generations.
Discover the Argos Olympus Collection
The jewels you just read about: those tiny, essential bearings, are what power the Argos Olympus collection. Designed for those who appreciate mechanical quality, the Olympus series uses a dependable Caliber 2530 Automatic movement with 33 jewels. This high jewel count is well above standard, reflecting the precision and durability built into the mechanism.
The Olympus offers excellent value by including high-end features like a durable 316L Stainless Steel case, a virtually scratchproof Sapphire Crystal, and a captivating dial with a useful Power Reserve Indicator and a classic small seconds display. Whether you choose the steel bracelet or the leather strap, the Argos Olympus is a reliable mechanical watch built with attention to detail and designed for daily wear.
Explore the Argos Olympus Collection today and own a watch where every component is engineered for precision.
