Gene: have you seen the bottom mark?

[Linked Image from photos.smugmug.com]

The crossed lightning bolts was not used until post-1923

[Linked Image from photos.smugmug.com]

Could it be a V-C date code?

BTW: the single crowned PT indicates standard proof at 850 BAR = 12,328 psi. I assume the 12,090 above is by crushers. The modern CIP max. service pressure would be 780 BAR = 10,733 psi

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