INTRODUCTION

MUCH SCIENCE BEHIND THE WATCH CRYSTALS The watch cover, a piece of clear material that protects the dial and internals. So simple, yet so much science behind it. Welcome to Infinity Timewatch, and this guide will walk you through some of the common watch crystal types used to make the watch covers – So you know what you are getting for your watch.

1) ACRYLIC

Scratch Resistance Weak Shatter Resistance Strong Cost Very Affordable

The chemical name for acrylic is polymethyl methacrylate (PMMA), and simply put, it is clear plastic. Acrylic is easy to shape and cheap to manufacture – Which is why most affordable watches use acrylic instead of glass. Sadly, acrylic is not as scratch resistant as glass. But on the plus side, it does not shatter as easily as glass, it is very light and it is cheap to repair. Usually, Acrylic glasses are found in Accutron, Bulova, Omega and Seiko watch brands. I would suggest getting a watch that has an Acrylic crystal if you are getting watches for your kids because they can be super clumsy when handling a watch.

2) PLEXIGLAS

Some of you guys may have already heard of this. Plexiglas, is in reality, a brand of acrylic (PMMA). So yes, Plexiglas® is essentially acrylic. Source – Akriform.

3) MINERAL GLASS

Scratch Resistance Strong Shatter Resistance Decently Good Cost Affordable

Mineral glass is a common material used in watch faces. Mineral glass usually is a lot harder than Acrylic glass and most mid-range watches are made of mineral glass. It has been heated, treated and hardened to better resist scratches. While it is much more scratch resistant than plastics, it is also much more brittle – It is more likely to shatter than plastics. Extreme hot and cold conditions may also cause the mineral glass to shatter. Even though mineral glass is a bit more expensive than Acrylic glass, they are still affordable especially with the high demand of replaceable mineral glass.

4) HARDLEX

Scratch Resistance Strong Shatter Resistance Decently Good Cost Affordable

Hardlex is Seiko’s brand of mineral glass. Is it any good? From most of the feedback from the Internet – It does seem to do decently good, and not many complaints from Seiko watch owners. Most Seiko watches that has Hardlex glass does not have an anti-reflective (AR) coating compared to Mineral glass. Hardlex glass is rated 7 out of 10 according to the Mohs hardness scale and they are cheaper than their Sapphlex glass.

5) GORILLA GLASS

Scratch Resistance Strong Shatter Resistance Moderate Cost Affordable

The “modern-day glass” which is made by Corning that is commonly used on smartphones, tablets, and even smartwatches. Not only they are lightweight, they are also quite strong. Gorilla glass is a good balance between cost and quality – Specially made to withstand fingernails and keys. As you might have heard, it seems to do pretty well against scratches but shatters when dropped from a certain height. The newer generations of Gorilla glass seems to be becoming better though.

6) SAPPHIRE GLASS

Scratch Resistance Very Strong Shatter Resistance Decently Good Cost Expensive

Touted as one of the best watch crystals… and very expensive. Sapphire glass is constructed using crystallized aluminum oxide. Sapphire glass is super scratch resistant, and it is nearly impossible to damage with your fingernails, keys and even pen knives; It can take some real punishments such as diamonds and other sapphires which is why most high-end watches contains sapphire glass. But do take note, even though sapphire glass is very rugged, it is not indestructible. Given enough force, you can still scratch and shatter it. If you bought a watch that is made up of sapphire glass, you basically have the highest quality glass as of right now. It is also rated 9 out of 10 according to the Mohs hardness scale. Replacing a sapphire glass is very expensive but the chances of replacement are quite rare.

7) SAPPHLEX

Scratch Resistance Very Strong Shatter Resistance Decently Good Cost Expensive, but less than sapphire glass

Sapphlex is Seiko’s hybrid sapphire-mineral glass. It has slightly better scratch resistance than the regular Joe mineral glass, but also costs slightly more… Although not as much as the “full” sapphire glass. Overall a good balance between price and durability.