What Are Jewels in a Watch? (Watch Jewels Explained)

If you’ve ever wondered what jewels are in watches, keep reading. Here’s what you need to know.

You know when you’re reading a watch movement’s description, and it gives you a jewel count? For example, “this Swiss Made caliber is a 25-jewel workhorse” or “Through the exhibition case back, you can see a beautiful mix of synthetic rubies and sapphires” — you get it.

Why add these adornments to a watch without a case back? Well, it’s because they’re more than just pretty decorations. However, they are nice to look at. So, what are jewels in watches? Do they do anything? Let’s get into it!

What Are Watch Jewels 

Watch jewels are synthetic jewels, often sapphires or rubies, placed in different parts of the movement. Their main job is to reduce friction between pieces that rub against each other.

Keep in mind that this is a very different thing than precious stones that are placed for decoration. For example, if there are gems on the dial or bezel, don’t refer to them as watch jewels in conversation — you’ll confuse whoever you’re talking to. 

The diamonds on a bedazzled Chanel J12 or the rubies set on a Cosmograph’s bezel? Not jewels. Well, they’re jewels, but you’ll want to refer to them as gem settings. The phrase watch jewel is reserved for the functional ruby and sapphire simulations placed within the movement of the watch. 

So again, because it’s so important, gem settings: Decorations on the watch (usually the dial, bezel, or even the bracelet). Watch jewels: Pieces placed in the movement to reduce friction.

What Are Jewels Used for in Watches 

Again, watch jewels are set into parts of the movement where friction happens.

Placing them where parts move against each other, such as gears and pivots, prevents wear and tear, as well as accuracy variation.

Different Types of Jewels 

Different types of jewels help with different parts of the watch. Some are even designed to work together. Here are some to know.

By the way, if some of the movement terminology is over your head, check out our guide on watch movements!

Pallet Jewel 

A Pallet jewel is a prism-like piece shaped like a rectangle. This makes it easier to place on each side of the pallet fork, which is the part of the escapement that moves back and forth with the escape wheel. 

This then powers the balance wheel, which keeps time. Suffice it to say you don’t want a lot of friction in this area.

Hole Jewel 

Also known as a pierced jewel, this type has a hole in it so that a watchmaker can mount it on the wheel’s axle.

It works with a cap jewel to create a pivot bearing, which allows the axle to rotate. The pivot bearing can also be used to prevent shock on a balance staff.

Cap Jewel 

A cap jewel doesn’t have a hole in it. Again, it works with the hole jewel to protect the balance staff and allow the wheel’s axle to spin.

Roller Jewel 

A roller jewel is shaped like a half cylinder. It’s placed between the pallets and the escape wheel.

Jewel Count 

So, what’s the importance of jewel count? Is it really the more, the better? It seems like it since Rolex movements usually have anywhere from 31 to 52 jewels, and they never even exhibit their calibers.

Of course, the less friction, the better, so the quick answer is yes, more jewels are better.

A watch movement with 17 jewels is considered a fully jeweled watch. This is because it covers all of the basic friction spots, from the balance wheel to the middle wheel pivot.

When a watch has 21 jewels, that means extra bearings are set in place to correct positional errors.

Beyond that, more jewels are needed if the watch has complications. A chronograph will have more moving parts inside of it than a basic timekeeper. More moving parts means more places for potential friction and more potential for positional errors.

If a watchmaker builds a chronograph and only adds bearings to the timekeeping component, then you’ll have a great watch but, possibly, a not-so-great stopwatch — or at least one that may need premature servicing.

Also, thin watches usually flaunt more jewels because they need high surface tension to stay connected to bearings, which causes more friction.

However, some argue that while additional jewels are beneficial, there is a bit of a diminishing return. So perhaps a watch with 45 jewels isn’t that much better than one with 50. Ultimately, what matters is how well-built the overall watch really is.

Here’s a list of places within the movement that benefit from watch jewels:

• The balance wheel
• The center wheel
• The escape lever (and its pallet)
• The staff pivot (remember that a hole jewel and cap jewel are placed here together)
• The escape wheel
• The fourth and third wheels in the gear train. The fourth wheel makes one revolution every minute, and the third wheel helps it do this,

Again, feel free to refer to our watch movement and terminology guides if you need extra clarity on these parts. We’ve got tons!

FAQs 

Have some leftover curiosities about watch jewels? Here are some quick answers to common questions.

How Many Jewels in a Watch Is Good?

A watch with 17 jewels is considered a completely jeweled watch. If it has 21 jewels, it means the movement is less likely to exhibit timing errors and rate differences. Of course, the more jewels in a watch, the less potential friction.

Are the Jewels Inside a Watch Worth Anything?

No, these days, most of the rubies and sapphires in a watch are synthetic. 

Do Quartz Watches Have Jewels?

Quartz watches can have jewels since there are moving parts in there. However, they don’t have as much as mechanical watches and will have significantly fewer jewels, if any at all.

Conclusion: The Historical Importance of Watch Jewels

Watch jewels have been placed in movements since the days of the pocket watch. Basically, they’ve been there since day one, or at least soon after.

They were developed by Swiss inventor Nicolas Fatio de Duillier, along with brothers Jacob and Peter Debaufre, in the 1700s. Of course, they originally used real rubies, making jeweled watches more expensive.

This is because rubies have a high hardness rate on the Mohs scale, rated a 9, just behind diamonds. These days, lab-made synthetic jewels are obviously more cost-efficient.

A connection to history, along with style and engineering, is one of the reasons we love watches. So, regardless of how many jewels a well-made movement needs or doesn’t need, it provides a sense of old-world watchmaking.

Do you like seeing the jewels through an exhibition case? Let us know in the comments!