• Apprentice
    17 Jul 2015, 8:39 a.m.

    Dear Users,

    I own an IWC Mark XV, which I haven't been wearing for some time. Last Night I recognized that there is no fluorescence on my watch hands what makes it impossible to read the time. The Marks at 12,3,6 and 9 are still shining bright. I had the watch for Revision but they did not say anything about fitting in new watch hands.
    So my question is; Is it normal that they lose their fluorescence from time to time?

    Thank you

  • Master
    17 Jul 2015, 10:58 a.m.

    Probably the hands used Tritium for luminescense which has aged too much already.
    Do you have at the bottom of your dial below number 6 the words
    [ul]
    [li]Swiss Made[/li]
    [li]T Swiss Made T[/li]
    [/ul]
    ?
    The latter says it uses Tritium.

  • Apprentice
    17 Jul 2015, 12:56 p.m.

    Yes,
    It does say T Swiss T.
    Tritium, of course..
    Thank you for the answer, Tilo.

    Cheers

  • Master
    17 Jul 2015, 1:52 p.m.

    I just asked because the Mark XV featured both versions:
    The early ones used Tritium for luminescence which is only very little radioactive and the new ones the Superluminova which is not radioactive at all. The Tritium has a half-life of about 12 years. That's why it looses its luminiescence over the years. Probably the hands had a thinner coatining with luminous material than the markers on the dial.
    I think I even saw watches that mixed somehow Tritium and Superluminova between dial and hands. If this was originally done by IWC I wouldn't be able to tell. Or if it was done during service (by IWC or someone else)? All a bit speculative but possible explanations...

  • Master
    17 Jul 2015, 2:01 p.m.

    Hi Tilo,
    right, the UTC Classic 3251 had the odd T/SL mix for a short period ex IWC.
    Cheers to BS @ 36 degrees in SH.

  • Connoisseur
    17 Jul 2015, 3:18 p.m.

    Hi, and welcome to the forum.

    The service centre would only offer hands if they are scratched or damaged. They have no way of testing for luminosity so the owner needs to mention their observations when first sending it for repair.
    You can still have new, superluminova, hands fitted but this would incur a maintenance service charge for fitting and resealing + a charge for the hands.
    Leo