Protecting every watch’s dial is a watch crystal, sometimes referred to as a watch glass.
A watch crystal is the clear part of the watch covering the dial.
There are three main types of watch crystals: Acrylic, Mineral or Sapphire Crystal.
We will also explore a lesser known watch crystal called Sapphire-coated mineral crystal too.
This blog post will also explore the pros and cons of each type of watch crystal and how they are different from one another.
If you need a quick breakdown of the types of watch crystals, then go straight to our:
You can also check out our Watch Crystal FAQ section at the end too. Which will show you how to find out the type of crystal of your own watch.
- What are watch crystals?
- Is it a watch crystal or a watch glass?
- How do you tell if a watch crystal is glass or plastic?
- How do you tell if a watch crystal is mineral or sapphire?
- Which watch crystal is the most durable and best quality?
- What is the best crystal for a watch?
Different Types of Watch Crystals
1. Acrylic Crystal
Also known as Acrylic Glass, Plexiglass, or simply plastic.
Acrylic crystal is a form of plastic that is very inexpensive and is popular on affordable or vintage style watches.
Acrylic crystal is very easy to manipulate, so watchmakers can use it to easily create any shapes that they want. Such as domed effect, which gives a distortion to the dial from a certain angle.
Acrylic crystal is also very cheap. That’s why you’ll see this watch crystal used on cheap watches. Which often gives this watch crystal a bad reputation.
However, most watches used acrylic crystal before the 1970s, and many even before the 1980s. Leading Swiss luxury watch brands like Rolex used acrylic crystal like everyone else during this time.
Rolex didn’t start using Sapphire crystal in their Submariner collection until 1979! So acrylic crystal is very common with vintage timepieces.
The main drawback with acrylic crystal is that it has low scratch resistance. This type of watch crystal can get easily scratched or marked.
However, this type of watch crystal is the easiest to buff out. You can even try buffing out the acrylic watch crystal at home.
However, thanks to the crystal’s flexibility, it can also handle heavy impacts quite well. This is why many military watches use acrylic crystal instead of other types of watch crystals.
2. Mineral Crystal
Mineral crystal is also referred to as mineral glass, or also Hardlex.
This watch crystal is the same glass that’s found in your windows. So it’s like a regular type of glass. Which makes it cheap for watch brands to source and manufacture.
Mineral crystal is a popular type of watch crystal for many affordable watch brands. Or watch brands who want to keep costs low.
It’s cheap like acrylic crystal, but it has more scratch resistance, and mineral glass. However, it still isn’t great. Especially when you compare it to sapphire crystal.
3. Sapphire Crystal
Sapphire crystal is by far the most popular type of watch crystal, as it has the highest level of scratch resistance.
This type of watch crystal is the chosen crystal of the luxury watch brands, and mid-range watch brands too. Even Orient uses sapphire crystal in their affordable Kamasu dive watch range.
Only a diamond will likely be able to scratch a sapphire crystal.
However, a downside is that sapphire crystal does run the risk of shattering if it has had a very heavy impact.
This means that many military watch brands often use acrylic crystal for their watches. As acrylic crystal can often handle very heavy impacts much better. Due to its flexibility, something that sapphire crystal does not have.
Yet, this type of watch crystal is much more reflective and shiny. Often looking the most expensive out of all the watch crystals.
And sapphire is by far the most expensive type of watch crystal too.
4. Sapphire-Coated Mineral Crystal
Sapphire-coated mineral crystal is a more recent watch crystal innovation. Also referred to as a sapphire-coated mineral glass. This type of watch crystal was gaining in popularity.
However, with the production costs of sapphire crystal falling, so too has its popularity.
A sapphire-coated mineral crystal is seen as a mid range crystal, in between mineral glass and sapphire crystal.
This crystal is essentially a mineral crystal with a special coating of sapphire crystal applied to it.
Seiko have famously used this type of watch crystal, calling it the Sapphlex.
This product will never be as scratch resistant as the real deal sapphire crystal, however, it will provide overall better scratch resistance compared to the mineral crystal.
Also it’s a more affordable type of watch crystal compared with sapphire crystal.
Acrylic vs Mineral vs Sapphire Crystal Comparison Chart
Here is a comparison of each of the three main watch crystals; acrylic crystal, mineral crystal, and sapphire crystal.
|Acrylic Crystal||Mineral Crystal||Sapphire Crystal|
|Shock resistance||Flexible watch crystal (so can handle very heavy impacts well)||Strong (but can chip with very heavy impacts)||Very Strong (risk of shattering with very heavy impacts)|
● Flexible glass allows for more diverse shapes
● Can handle heavy impacts due to flexibility
● Easier to buff out scratches
● More scratch resistant than acrylic
● Less reflective compared to sapphire
|● Very, very high scratch resistance (only diamonds could scratch it)|
● Looks more expensive
● Most popular type of watch crystal for luxury watches
|Cons||● Some say it looks cheap (very subjective)|
● Very easily scratched or marked
|● Not as scratch resistant as sapphire|
● Can chip with heavy impacts
● Often needs to be replaced when damaged
● May shatter with very heavy impacts
● Highly reflective (some say this can hinder readability from certain angles)
● Often needs to be replaced when damaged
Nowadays, most people would choose a sapphire crystal for their watch. It has by far the best level of scratch resistance, it looks more expensive, and overall it’s the strongest crystal for a watch right now.
However, Sapphire Crystal is expensive.
So if you’re on a budget, the majority of entry level watches will go for the cheaper option of mineral crystal or acrylic crystal can be the other options.
As the comparison chart outlines above. Each of these types of watch crystals have their pros and cons. None of them are perfect for all styles of watches or situations.
So just go by what you need and want from your timepiece.
Watch Crystals FAQ
What are watch crystals?
Watch crystals refer to the clear portion of the watch that protects the dial.
Is it a watch crystal or a watch glass?
Why do we call it a watch crystal, instead of a watch glass?
The reason is because not all watch crystals are made of glass. Such as acrylic crystal which is made from plastic. While sapphire crystal isn’t technically made of glass either.
However, mineral crystal is made from glass, and can be referred to as mineral glass.
So the correct term is always watch crystal, but people will still understand you if you refer to it as a watch glass.
How do you tell if a watch crystal is glass or plastic?
How to tell if a watch crystal is glass or plastic is by rubbing your finger across the crystal.
First before doing the test, give your watch a clean so that the crystal is shiny.
Then take your watch crystal, and press your finger against the crystal. Hold your finger down and move your finger side to side.
If you hear a noise, like a squeaky noise, then the watch crystal is plastic. Meaning it’s an acrylic crystal.
But if there is no noise when you do this test, then the watch crystal is made from a type of glass, so it could be either a mineral crystal or a sapphire crystal.
How do you tell if a watch crystal is mineral or sapphire?
A handy test to tell if your watch has a mineral or a sapphire crystal. Is by putting a few drops of water on the crystal and watching how it reacts.
If the water slides off and has only a couple of small drops stuck to it. Then the watch crystal is a sapphire crystal.
Whereas, on the mineral crystal, most of the water will stick and spread across the surface instead.
Which watch crystal is the most durable and best quality?
Sapphire crystal is the most durable and best quality watch crystal available today. It’s the most scratch resistant.
However, it’s also the most expensive type of watch crystal.
What is the best crystal for a watch?
Sapphire crystal is considered the best crystal for a watch today. This is due to sapphire crystal’s super levels of scratch resistance.