This morning, as is an enjoyable weekend routine for me, I went through my cleaning ritual with my watches. As I was dutifully wiping down my Apollo 45th, I ended up spotting a line of etching on the gold bezel I had not noticed before!! It is on the underside of the gold rimmed bezel at the 12 o'clock position. As I started nerding out on a new found aspect of my beloved watch, I attempted to identify what was written. With the naked eye, from left to right, I was able to make out the Omega symbol followed by Au 750...awesome! However, there are two other symbols after the Au 750 which I cannot identify. I have attempted using the loup which comes with the Speedy Pro, no luck. Next, I took a pic with my phone camera and have been playing with zoom and lighting...still no luck!

It is possible that my Googlefu is failing me. However, I have been unable to locate any mention of this engraving let alone what it is. Even my go to and always enjoyed @Robert-Jan and Fratellowatches has no mention!

Ergo, I am turning to my fellow Omega forumites for aid. Anyone with this watch have a higher powered camera or loup which may assist in identifying the mystery etching? Below is the best picture which I am personally able to take and enhance.

 

Seems like certain jewelry are etched with that to signify what precious metal was used. I believe from trusty wikipedia it means 18kt gold. My google search does not yield that any other code to express fineness is needed (no idea what the last marking is). Pretty cool, anyone with a macro lens want to post more pictures ! More please !

source : https://en.wikipedia.org/wiki/Fineness

 

They are called hallmarks, it's not just specific to omega but gold, silver etc in general. I can't make out the picture. Try using your loupe with the camera.

Edit:
Here's a link with more information http://www.langantiques.com/university/Jewelry_Identification

 

Just had look with my loupe. Hard to take photo but 2nd in from right is St Bernard Dog , which is Swiss Assay Office hallmark. There will be a tiny letter also engraved bottom right of it to signify which office marked it.
The furthest right mark is the number 750 in centre of a set of scales, signifying 18k gold.

 

You need a decent camera. Smartphones suck.



Here is another one I just made in the kitchen. It shows the right two symbols more clearly:

 

Fantastic macro photo @hkrauss .
The T apparently means it was stamped at Chiasso assay office, according to info on web.

I love these little posts that add a treasure hunt to a lazy Sunday.

 

Thank you guys very much for helping me with the answers! Special thanks to @hkrauss for those amazing macro shots!!

I am still surprised that I didn't notice these symbols until yesterday. Am I the only owner whom had been oblivious to these particular etchings?

 

I've never noticed them either, pretty cool detail! I tried to grab a macro shot yesterday but can't get the right angle with my phone + olloclip.

 

Oddly, the Swiss standard mark shown in some references for 18-karat gold is a profile of the goddess Helvetia. Can anyone explain the (apparent) standard mark of a St. Bernard dog?

 

Try this link
http://theswissmonster.blogspot.de/2011/10/know-your-swiss-hallmarks.html
"After 1995 the Swiss hallmark for gold became a St. Bernard"

 

Indeed! That explains it. Thanks. My source needs to be updated.

 

FIFY

 

it has to do with the karat of gold, symbolizing 18 k with 75% gold and alloyed with other materials as well.
your specific bezel is alloyed with palladium and copper

 

I was completely unware @Bushido until you posted. Only got round to looking at my XI-45 today with an Omega "swag" loupe. @hkrauss did a superb job with his macro lens!