What is Hardlex Crystal?

Once you learn different watch crystal types, choosing the perfect glass becomes as important as the complications, or the brand.

One such popular crystal type is Seiko’s Hardlex crystal. The Japanese watchmaker has been using this crystal for decades, and it’s a great choice for affordable watches.

Let’s explore this “poor man’s sapphire”; in everything from its history to its comparison with other crystal types.

What is Hardlex Crystal?

Hardlex crystal is a proprietary material developed by Seiko, a Japanese watchmaking company renowned for its innovation and quality.

Introduced in the 1960s, Hardlex Crystal was conceived to offer a more affordable and robust alternative to traditional watch crystals.

It is a type of mineral glass that undergoes a special hardening process, which increases its resistance to knocks and scratches.

The manufacturing process involves heating the mineral glass to high temperatures and then rapidly cooling it, a method known as tempering.

This results in a crystal significantly tougher than standard mineral glass, though not as scratch-resistant as sapphire crystal.

Over the years, Hardlex crystal has become a hallmark of Seiko watches, lauded for its balance between durability, clarity, and affordability.

It has found its niche, especially in Seiko’s sports watches, where a balance between toughness and cost is critical.

Properties and Advantages of Hardlex Crystal

Hardlex crystal exhibits some distinctive properties setting it apart in the watchmaking industry.

One of the key properties is its impressive impact resistance. This makes it a great choice for use in sports and everyday wear.

Another noteworthy property of Hardlex crystal is its enhanced scratch resistance, although not the best one in the industry.

In some higher-end Seiko watches, the Hardlex crystal comes with an anti-reflective (AR) coating.

This AR coating reduces light reflection on the surface of the crystal, enhancing the legibility of the watch under various lighting conditions.

The advantages of Hardlex crystal extend beyond its physical properties.

The manufacturing process of Hardlex crystal allows it to be offered at a lower price point than sapphire crystal.

This affordability doesn’t compromise the quality or durability of the watch, making Hardlex-equipped watches an excellent value proposition.

Furthermore, if a Hardlex crystal does get scratched or damaged, it is typically less expensive to replace than sapphire crystal — another plus for budget-conscious watch enthusiasts.

On average you can expect Hardlex Crystal replacement to be around $30-$70, excluding the service charges.

Comparison to Other Watch Crystals

While Hardlex crystal offers a good balance of durability and affordability, where does it stand in comparison to other popular watch crystals?

Let’s take a closer look at some of the main contenders.

Hardlex vs. Acrylic Crystal

Acrylic crystal, also known as Hesalite, is a type of plastic that was once a common choice for watch crystals, particularly during the mid-20th century.

It is prized for its incredibly low cost and high-impact resistance.

However, compared to Hardlex, acrylic is much more prone to scratches and scuffs, although these can often be polished out.

On the other hand, Hardlex provides a marked improvement in scratch resistance while maintaining an excellent degree of shatter resistance.

Hardlex superior hardness means that it’s unlikely to be marred by all but the most severe impacts, a quality that acrylic does not possess.

While acrylic may offer a softer and warmer look to the dial, Hardlex crystal excels in the domains of strength and durability.

Therefore, consider hardlex, an overall better choice compared to acrylic crystals.

Hardlex vs. Mineral Glass

Mineral Glass is perhaps the closest competitor to Hardlex in terms of properties and price point.

It is a common choice for mid-range watches due to its reasonable scratch resistance and decent impact tolerance.

However, when comparing Mineral Glass to Hardlex, the latter edges out in terms of toughness.

The special tempering process that Hardlex undergoes equips it with superior scratch resistance and impact tolerance compared to standard Mineral Glass.

Despite this, it’s worth mentioning that both these crystals can be scratched by materials that rank higher on the Mohs scale of hardness.

However, such instances are relatively rare in everyday scenarios.

Thus, between Hardlex and Mineral Glass, the former stands out as a more durable, albeit slightly more expensive, option.

Hardlex vs. Sapphire Crystal

When comparing Hardlex and Sapphire Crystal, the latter often takes the upper hand in terms of scratch resistance.

Sapphire Crystal is virtually scratch-proof, boasting a rating of 9 on the Mohs scale of mineral hardness — second to diamond.

However, Sapphire Crystal’s greater hardness also makes it more brittle and prone to shattering on impact.

On the other hand, Hardlex, while not quite as scratch-resistant as Sapphire Crystal (7 rating on the Mohs scale), offers superior impact resistance.

Its tempered structure allows it to shrug off knocks and blows that might crack or shatter a more brittle crystal.

This balance of properties makes Hardlex suitable for situations where watches may be subject to physical stress, like sports or outdoor activities.

In terms of visual appeal, both Hardlex and Sapphire Crystal offer distinct qualities.

Sapphire Crystal is noted for its exceptional clarity and the clean, crisp visuals it provides.

Hardlex, while not quite as transparent, compensates with the optional addition of an anti-reflective coating that enhances visibility in a wide range of lighting conditions.

When considering cost, Hardlex is a clear winner.

The manufacturing process of Hardlex is more cost-effective than that of Sapphire Crystal. So, watches with Hardlex crystals are more affordable without compromising on durability or quality.

Why does Seiko Use Hardlex Instead of Sapphire?

Seiko has a reputation for using Hardlex crystal in their watches, even in models with higher price points like the Prospex and Presage lines.

So, why does Seiko continue to use Hardlex instead of opting for the seemingly superior Sapphire Crystal?

The answer lies in Seiko’s philosophy of bringing high-quality watches at affordable prices to a wider market.

The manufacturing process of Hardlex allows it to be offered at a lower price point than sapphire crystal without sacrificing durability or quality.

Therefore, Seiko can keep its watch prices competitive while still providing excellent timepieces that are built to last.

Additionally, Hardlex Crystal aligns with Seiko’s focus on practicality and functionality in their watches.

I hate to say that when choosing the watch, crystal isn’t the primary focus for most gentlemen.

Therefore, Seiko can easily get away with using somewhat lesser-quality crystal, as long as the movement is good.

When to Choose Hardlex Crystal

Choosing the right watch crystal depends on many factors, including personal preference and intended use.

Here are some situations where Hardlex crystal may be the best choice:

• If you’re on a budget and looking for an affordable watch that can withstand everyday wear.
• If you engage in activities that might put your watch at risk of impact or scratches, like sports or outdoor adventures.
• If you prefer a slightly warmer and less reflective look to your watch dial than what sapphire crystal provides.
• If you want a durable, low-maintenance watch without having to pay the premium price of Sapphire Crystal.

Given its balance of affordability and durability, it’s easy to see why many Seiko watches continue to feature hardlex crystal.

Popular Seiko Models with Hardlex Crystal

Seiko offers a wide range of models featuring Hardlex crystal, catering to different tastes and needs. From the iconic SKX007 diver to the elegant SUR539, you can find Hardlex on everything from casual to professional timepieces.

• Seiko SKX007: A classic diver’s watch, the SKX007 is celebrated for its robustness and timeless design.
• Seiko SNK803: This affordable automatic watch is a gateway into the world of serious watch collecting and showcases a Hardlex crystal on a budget.
• Seiko SUR539 & SUR540: Part of the Seiko Core collection, these watches combine contemporary design with Hardlex durability.
• Seiko Prospex: Many of Seiko’s Prospex line, especially the diving watches, feature the Hardlex crystal due to its underwater performance.
• Seiko 5 Sports: The Seiko 5 Sports models offer a sports watch with a hint of heritage, often with Hardlex crystals to provide that added protection against the elements.

Tips for Maintaining Hardlex Crystal

Preserving the integrity of your Hardlex crystal doesn’t require much, but some simple tips can ensure it looks its best for years to come:

1. Regular Cleaning: A soft, lint-free cloth slightly dampened with water will remove everyday dirt and smudges.
2. Avoid Abrasives: Steer clear of rough materials when cleaning the crystal; Hardlex may be scratch-resistant, but it’s not invincible.
3. Protect from Impact: While Hardlex is tough, avoid unnecessary impacts that could damage the crystal.

Conclusion

Hardlex crystal offers a balance of durability, affordability, and practicality that makes it a popular choice for Seiko watches.

While Sapphire Crystal may have slightly better scratch resistance, Hardlex provides superior impact resistance at a lower cost.

Seiko continues to use Hardlex in many of its models to cater to customers looking for dependable and long-lasting timepieces without breaking the bank.