We have summarized the features of the three types of windshields: "sapphire glass," "mineral glass," and "plastic windshield."

The crystal protects the dial and movement from dust, water, and other contaminants, as well as shocks, water pressure, and light reflection.

At first glance it just looks like "glass," but its characteristics, such as durability and appearance, vary greatly depending on the material.

There are three types of glass generally used in luxury watches, and their usage differs according to cost and design.

• Sapphire
• Mineral glass
• Plastic windshield

We will explain these features today so that you can use them as a reference when choosing a watch.

Please note that popular watches sell out quickly.

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Characteristics of sapphire glass

First, let us explain the characteristics of sapphire glass, which is used in luxury watches.

The defining feature of sapphire glass is that it is extremely hard!

Sapphire glass is the most commonly used glass in luxury watches .

It is also known as "sapphire crystal."

By the way, it is called glass for convenience only; it is not actually glass. It is a material made by heating artificial sapphire powder to 2000℃ with a hydrogen burner, melting it, and crystallizing it.

Sapphire crystal has the same hardness as the natural gemstone sapphire (Mohs hardness*: 9) and is highly scratch-resistant .

*Mohs hardness: Mohs hardness is a scale that indicates the hardness of minerals. It is rated on a scale of 1 to 10, with 10 being the harder the stone.

An example of a luxury watch that uses it is the Rolex Explorer I.

Except for the production period around the 1960s, Rolex watches have used sapphire crystal for their crystals.

Compared to the plastic crystal described below, sapphire glass does not have raised sides.

Many of the watches we carry, including Rolex, Patek Philippe, and Audemars Piguet, are made with sapphire glass.

Points to note: "Costly" and "When it breaks, it breaks spectacularly"

On the other hand, there are also disadvantages such as it being expensive and breaking dramatically when it does break .

To briefly explain each one, the former has excellent properties but is very costly to process .

For this reason, although it is an ideal material for watch glass, it is only used in luxury watches .

Regarding the latter, generally the harder the material, the more spectacularly it will crack.

It is unlikely that it will break in everyday life, but you should be careful not to subject it to strong impacts such as hitting it against concrete.

Characteristics of mineral glass

We have briefly summarized the characteristics of mineral glass , which is mainly used in watches under 50,000 yen .

This type of glass is not generally used in the watches we sell, but it is an essential glass when it comes to understanding the types of crystals.

Mineral glass is "common" glass

Mineral glass is a common type of glass.

Although mineral glass is not as hard as sapphire glass (Mohs hardness: 3 to 6), it is inexpensive and easy to process, and is used in many watches, including casual watches.

Note: Small scratches are difficult to repair.

One thing to note about mineral glass is that it cannot be maintained by polishing, as is the case with the plastic crystal described below , so even small scratches will remain.

Also, because it is made of ordinary glass, if it is subjected to a strong impact it may chip or break, and there is a risk of damaging the dial .

Features of plastic windshield

Finally, we will discuss the features and precautions regarding plastic wind shields.

A plastic windshield is a windshield made of plastic, sometimes called a "plastic windshield" or trademarked as "plexiglass."

It is a material with a very long history, having been used since the dawn of wristwatches.

It was widely used in watches from the 1940s to 1960s, but gradually fell out of use around 1970 as glass became more widely used to cover watch dials.

For this reason , plastic windshields are generally used on many vintage items .

The dome-shaped plastic windshield is attractive!

The most attractive feature of the plastic windshield is its shape.

Glass is a hard material that is difficult to process, which is why it has a flat surface.

On the other hand, plastic windshields often have a curved, dome-shaped design to increase strength, and this shape is very unique .

The domed shape is a symbol of antique watches , and many collectors enjoy the feel of the edges.

For example, if you look at a photo of a vintage Rolex, such as a Rolex Submariner , you will notice that the crystal is dome-shaped.

This Submariner is from around 1965.

You can see that it is more clearly raised when viewed from the side.

Our store only sells Rolex watches under the category of " Vintage Rolex ."

Thus, Rolex is also known as a watch with high asset value.

There are brands that use plastic crystals not only for vintage items but also for current luxury watches .

Some of the most well-known brands include Panerai and Omega .

This Panerai Radiomir was manufactured in 2012, but has a plastic crystal (plexiglass).

You will be instantly drawn in by the domed crystal that protects the dial.

This Omega Speedmaster was also manufactured in 2003, but it uses a plastic crystal (Hesalite).

The Speedmaster, which is said to be the face of Omega, is a series that survived rigorous testing during the intensifying space race at the time and was officially adopted as official equipment by NASA.

This limited edition Snoopy model is a collaboration between "space" and "Snoopy," two things that at first glance seem to have no connection, but there is a deep connection between the two through space development.

In 1967, a fire broke out during training on the Apollo 1, killing three astronauts. NASA's space program came under public criticism, as it seemed to disregard human life.

NASA chose Snoopy as a "symbol of safety and security" to ensure that such a tragic accident will never be repeated.

The plastic windshield, which is close to the specifications of the time, shows the commitment to the collaboration.

As such, plastic windshields are not only used as vintage items, but are still used today due to their high design quality.

We carry a wide range of products in our store, so be sure to check out our purchase page.

Note: Shallow scratches can be buffed out, but scratches are still likely to occur.

The Mohs hardness of plastic windshields is around 2, which is about as hard as a human fingernail or amber.

Because it is a soft material, it has a feature not found in other windshield materials in that shallow scratches can be polished away , but it is still prone to scratches.

Types of windshields: Summary

A crystal is used to protect the dial of a watch .

This time, we will introduce three types of crystals: sapphire glass, mineral glass, and plastic crystal, and summarize their features and points to note .

First of all, sapphire glass is a material that is often used in luxury watches, with a Mohs hardness rating of 9.

While its hardness has the advantage of making it less susceptible to scratches, it also has the disadvantage of being costly.

Mineral glass has a Mohs hardness of 3 to 6 and is a commonly used material for watches.

It is widely used because it is ordinary glass, but it has the disadvantage of being more easily scratched than sapphire glass.

The last of these, plastic crystals , have the disadvantage of being less strong and more easily scratched than sapphire glass, but they have a unique charm that only plastic crystals have, making them a firm favorite among watch enthusiasts.

Many of the watches we sell are equipped with sapphire crystal, but some vintage and current Panerai and Omega models use plastic crystals.

We hope you will come and visit us and take a look at the watches we have in stock .

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Thank you for reading.

If you have a luxury watch you'd like to sell, please feel free to contact Commit Ginza!
If you want to buy luxury watches at a low price, be sure to come to Commit Ginza!

• "I want to sell my unused Rolex for as much as possible."
• "I want a thorough assessment."
• "I want to buy from a store with a good track record."
• "I want to buy luxury watches at low prices."

If you have these requirements, Commit Ginza is perfect for you !

Commit Ginza is a watch store that operates on the concept of " buy high, sell low " in the used watch market, where prices are said to be difficult to understand.

Our experienced watch appraisers assess the watches to determine the market value and set the appropriate price. We also strive to maximize the profit margins of our stores and improve customer satisfaction.

As a result, the commission rate for deposit sales is only 3%!! (The industry average is 10%)

Please feel free to consult with Commit Ginza whether you are purchasing a watch for investment or selling.