Rolex 1500 Due Diligence

[Eapfep]

Hey all,

I've been long enamoured with the vintage "stick hands, oyster case with smooth bezel" look, and after contemplating buying a Tudor, I've decided to get a Oyster Perpetual Date 1500 instead.

http://imgur.com/a/QGWDy

Here is the watch in question, I have a few questions about it, it would be awesome if somebody could help me answer some! Keep in mind that while I get a little nit picky, the ultimate goal for me is to wear this watch daily (and not lose out on too much of what I paid when/if I come around to upgrading to another watch).

- The dial is marked tritium lume, yet there are no signs of lume on the hands or dial. What is going on and does it damage the value of the watch?

- What is a "sigma" dial exactly?

Thanks!!

[Eapfep]

Oops, seems like I posted this twice (post must have been under review). Sorry mods!