What are the differences between a sapphire and an acrylic watch crystal?

What are the differences between a sapphire and an acrylic watch crystal?

The main difference between a sapphire and an acrylic watch crystal lies in the materials used and the resulting properties. Here are some key distinctions:

  1. Material :

    • Sapphire watch glass: Made from synthetic corundum crystal, sapphire is a very hard material. Sapphire is one of the hardest materials after diamond on the Mohs hardness scale.
    • Acrylic watch glass: Also known as plexiglass or hesalite, this is a transparent plastic material. It is less hard than sapphire.
  2. Hardness :
    • Sapphire watch glass: extremely hard and scratch-resistant. This is one of the reasons why it is widely used in high-end watches.
    • Acrylic watch glass: This is softer than sapphire and tends to scratch more easily.
  3. Clarity :

    • Sapphire watch glass: It has excellent optical clarity and is generally distortion-free.
    • Acrylic watch glass: It can sometimes show distortion, particularly over time and with exposure to light.
  4. Scratch resistance :

    • Sapphire watch glass: Highly scratch-resistant. It generally stays looking like new longer.
    • Acrylic watch glass: Less scratch-resistant than sapphire. Scratches may appear more easily, but they can also be more easily removed by polishing, which is not the case with sapphire.
  5. Fracture:

    • Sapphire watch glass: Although very hard, it can be broken or cracked in the event of violent impact, although this is relatively rare.
    • Acrylic watch glass: Less prone to breakage on impact.

In summary, the choice between sapphire and acrylic watch glass depends on personal preference, watch style and intended use. Luxury watches often have sapphire crystals because of their durability and high-end aesthetic, while vintage or casual watches may opt for acrylic for its retro look (usually domed) and ease of polishing.