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fsxlxz asked in Science & MathematicsPhysics · 2 decades ago

what is the hesalite crystal and the sapphire crystal? what is the differece?

3 Answers

  • Anonymous
    2 decades ago
    Favorite Answer

    You mean watch crystals, yes? Hesalite is the tradename for an advanced synthetic (plastic) crystal. It's an improvement over older acrylic crystals, but it's nowhere near as hard as sapphire. The advantages are that it's lighter, it's not as inherently shiny, so it has less glare, it's shatterproof, and if it gets scratched, you can polish out the scratches. Also, since it's easier to work, you're more likely to find glare reducing domed surfaces on a Hesalite crystal than a sapphire one, although many sapphire watch crystals are domed as well. It's just not as common.

    While sapphire can be chipped or shattered, it's very hard to do so. But, a blow that will shatter sapphire will only put a ding in Hesalite, one which it may or may not be possible to polish out, depending on how deep the ding is.

    Hesalite is used primarily on older Omega sports watches. It's a perfectly fine material. Even the older acrylics are fine. The modern style is towards use of sapphire crystals, and there's a lot of hype about them being unscratchable and so on, most of which is true, but Hesalite, or acrylic, is still a very suitable material for watch crystals. In many cases, if you're shopping for a vintage watch, an older model with an acrylic crystal will be much cheaper than a slightly newer one with a sapphire crystal. Also, many generic fit sapphire crystals are available today which can be retrofitted to something which originally had a plastic crystal, if you're really concerned about scratching.

    In practice, though, I've had no problems wearing older watches with high quality acrylic crystals. I wear several different watches, some with old acylic crystals as well as modern ones with sapphire, and I've seen no major performance differences. Yes, some small scratches do happen with plastic, but just get yourself a tube of Polywatch, or similar polishing paste, and you can remove them with a light buffing. Modern good quality sapphire, with domed surfaces and internal anti-reflective coatings can be very readable, but often the flat non-coated sapphire crystals will produce severe glare.

  • Anonymous
    4 years ago

    Domed Sapphire Crystal

  • 5 years ago

    Sapphire Watch Crystal

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