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"Bullseye" facet on 33.3 mineral crystal - Was that original? - Still available?

  1. MauiSurfBrah Sep 16, 2018

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    Hello,
    I have a 1938 33,3 CHRO which has a "bullet" facet in the center of the crystal. It is slightly concave, about 8.5mm in diameter.
    Would that have been original?
    Are crystals like that still available today? (Even in NOS inventories?)

    Thanks!
     
    Edited Sep 22, 2018
  2. MauiSurfBrah Sep 16, 2018

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    I really hope to find out that these crystals are still available [fingers crossed], but in all the searching I've done, I haven't found a thing about them. I might not be using the right terminology though. Also, the B2B side of watch repair/parts suppliers is completely foreign to me.

    Here's a link to a thread with some more info/questions on my watch, if anyone wants to chime in on any of the other aspects of it:
    Holy Grail 33.3 CHRO? Any more info? What should I do?

    :)
     
  3. Canuck Sep 16, 2018

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    I very much doubt your watch left the factory with that “bullseye” crystal on it. That type of crystal was used on watches in the 17th, 18th, and possibly early 19th centuries. The concave spot on your crystal was often called a “pontil” mark, or perhaps more popularly a “punty” mark. The jury is out on why those facets are there. Everybody with an explanation is adamant that there explanation is correct. So I’ll stay out of it. Best of luck finding a replacement.

    If you are desperate, you might check with White’s watch crystals, here:

    http://www.whitescrystals.com/products.html
     
    MauiSurfBrah likes this.
  4. MauiSurfBrah Sep 16, 2018

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    Thanks! That actually makes a lot of sense. I have now been able to find a bit more info about this type of crystal. I guess they used a pontil rod to hold the glass while they were working it, then ground it out after the piece was cooled.

    Does anyone who is familiar with 1930's 33.3 chrono's know if this was original?
     
  5. Tony C. Ωf Jury member Sep 16, 2018

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    I have seen such crystals on wristwatches even later than the '30s, though it's a mystery to me why they would have been used.

    I doubt very much whether they were ever used on 33.3 chronographs, but I could get an authoritative opinion later in the week.
     
  6. Fritz genuflects before the mighty quartzophobe Sep 16, 2018

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    "Daves Watch Parts"

    once on his page check under... wait for it... glass high and low dome crystals!

    worth a shot, he's provided me with a lot of vintage stuff over the part few years.
     
  7. Canuck Sep 16, 2018

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    With regard to why these crystals have a “bull’s eye”? Everyone who has an opinion is adamant that his is the only opinion that matters! I stay out of such discussions, after learning the hard way!