Identifying sodium filled valves

[G40 AD]

Just wondering if it is possible to identify sodium filled valves from standard? Got a head from a g conversion I bought a while back and a lot of the bits turnd out to incorrect/poor conditon... so basically I want to be certain the head contains the correct valves befre I have it rebuilt with the same valves in...

cheers

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[PeteG40]

they have a dot in the middle of the face

[Yoof]

Should be lighter too 

[PeteG40]

failing that they have a part no on the stem

[G40 AD]

Awesome will compare to some known g40 zorst valves bwfore it goes for a rebuild...

cheers

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