Omega SHOM dial question

Hi all

I have a question I’m hoping someone can help me with. I have an Omega SHOM dial that I’m sure is original, but it has no coating of any type on the markers. The rest of the dial is in great condition, so I’m assuming it’s either never had tritium/another light sensitive coating on it or it was supplied without.. possibly a service dial?

I know some original dials came with ‘T’ markings on the dial, for Tritium, and some came without the T… although I don’t know if the dials without a T on them had an alternative lume coating? or if they had no coating at all?

Can anyone help?

Thanks Andy