What Are Jewels?

What Are Jewels in a Watch?

In watchmaking, jewels are tiny pieces of synthetic ruby or sapphire used as bearings for moving parts. They’re not decorative (even though they do look pretty) — their role is purely functional. Watch movements have several metal components constantly rubbing against each other, and without lubrication or resistance control, friction would cause them to wear out quickly. Jewels are extremely hard, smooth, and wear-resistant, making them ideal for reducing friction and maintaining precision in mechanical movements over time.

What Do Jewels Actually Do?

Jewels are typically placed where there’s a lot of rotational movement or contact pressure, such as in the pivot points of gears or the escapement mechanism. The main goal is to reduce metal-on-metal contact. For example, a gear shaft (pivot) sits inside a jewel with a small oil reservoir. The jewel acts like a smooth track for the shaft to spin in with minimal resistance. This not only improves accuracy but also increases the lifespan of the movement. Think of them like the ball bearings in an engine — small parts doing big work behind the scenes.

How Do They Work Within the Movement?

In practice, jewels are press-fit into the watch plates or bridges. Pivots from the gear train or escapement rest inside the tiny holes of these jewels. There are different types:

• Hole jewels support rotating axles.

• Cap jewels (flat-topped) cover hole jewels to stabilize movement.

• Pallet jewels interact with the escape wheel in the escapement to control the release of energy.
  All are placed with micrometer-level precision to ensure optimal alignment and smooth function of the movement.

How Many Jewels Do Watches Have?

Basic mechanical watches typically have 17 jewels, covering essential pivot points and the escapement. More complex movements with automatic winding systems, chronographs, or calendars can have 21 to 40+ jewels. However, past a certain point, more jewels don’t necessarily mean better quality — sometimes they’re added for marketing purposes rather than function. What matters most is where the jewels are used and how well the movement is designed. The "24 Jewels" in our name "24 Jewels & Counting" comes from the major utilization of TMI NH series (Seiko) movements in our collections that primarily use 24 jewels. The "& Counting" in our name highlights the variety of jewels in the movements we use, like many of the 21 jewel Miyota movements or 0-5 jewel hybrid meca-quartz movements you may see, such as the popular VK63.

Are They Real Gems?

Technically, yes — but they’re lab-grown synthetic rubies, not natural gemstones. Natural jewels aren’t practical for watchmaking because they vary in purity, size, and consistency. Synthetic rubies are perfect: hard (rated 9 on the Mohs scale), consistent, and cheap to mass-produce. Since the 1900s, nearly all watch jewels have been synthetic. They might be small and unglamorous, but they’re vital for keeping a mechanical watch precise, durable, and smooth-running. Many luxury name brands, such as Rolex, Patek Philippe, Omega, and many more use synthetic rubies just like the ones you find in our watches, however, they may use more of them (30-40+ jewels) and of course case the movement in all kinds of precious stones, metals, and more to increase the sale price.