[Question] Is this Scratches on AR Coating or Sapphire Crystal?

tomatopotato · Jul 22, 2020

Hello,

I have been eyeing on 3520.50 Speedmaster Day Date (or 'Mark 40' or 'Triple Calendar') and came across a sale post from oversea's reputable retailer at a bargain. The watch has been overhauled and looks to be in a decent condition - except some scratches I see on the crystal:

There are some threads on this topic on WUS but no photos that demonstrate the distinction clearly. If it is in fact scratches on the AR coating rather than crystal, I will be pulling the trigger and remove the coating entirely, as I personally don't care for AR coating (all of my watches are actually with plexiglass). If it's on the crystal itself, it might be a deal breaker as it would cost a lot for Omega to replace it as I would like the watch to be legible without too much scratches.

Please let me know what you think, and thank you for your time.

Stay safe!

Joon from Florida

tomatopotato · Jul 22, 2020

This model seems to have outerside AR coating in fact:
"Told ya! 25 year old watches, a lot of the time the topside AR does not survive. The Mark 40s all seem to have topside AR coating, when watches that came before and shortly after 3521.xx, 3523.xx didn't seem to have them.. "

gbesq · Jul 23, 2020

I'm guessing that it's the AR coating. Although it can be done, it takes some work to put that many visible scratches on a sapphire crystal. It does make you wonder whether the plain old acrylic crystals that used to be standard on most watches are actually preferable to sapphire. With a bit of polywatch, it's easy to remove all but the most severe scratches from acrylic crystals, they don't shatter from a hard impact, and it's relatively inexpensive to replace them. With AR coated sapphire crystals, a scratch on the AR means either living with a dinged up crystal or removing the AR entirely. Sapphire will also shatter from a hard impact and all those shards of mineral glass can mess up the dial and sometimes get into the movement which then requires expensive servicing. For me, choosing a hesalite Speedy over the sapphire version was a no brainer.

tomatopotato · Jul 23, 2020

gbesq
I'm guessing that it's the AR coating. Although it can be done, it takes some work to put that many visible scratches on a sapphire crystal. It does make you wonder whether the plain old acrylic crystals that used to be standard on most watches are actually preferable to sapphire. With a bit of polywatch, it's easy to remove all but the most severe scratches from acrylic crystals, they don't shatter from a hard impact, and it's relatively inexpensive to replace them. With AR coated sapphire crystals, a scratch on the AR means either living with a dinged up crystal or removing the AR entirely. Sapphire will also shatter from a hard impact and all those shards of mineral glass can mess up the dial and sometimes get into the movement which then requires expensive servicing. For me, choosing a hesalite Speedy over the sapphire version was a no brainer.

I wholeheartedly agree with you, as this is precisely why most of my watches have plexiglass (but the only Omega I have is with sapphire, 1st gen Aqua Terra).

Thank you for sharing your opinion!

[Question] Is this Scratches on AR Coating or Sapphire Crystal?

tomatopotato

tomatopotato

gbesq

tomatopotato

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