Sweep seconds color: black vs heat-blued?

Hi all,
I’d like to ask for opinions regarding the correct central sweep seconds hand color on an Omega 27 CHRO 12, dating to circa 1942.

The watch has:

• Civil dial
• No lume
• Black printed numerals and scales
• Black hours and minutes (pavonized, not painted)
• Tricompax layout

I currently have two period-correct sweep seconds hands, both with counterweight:

1. One black pavonized
2. One heat-blued steel, very dark, appearing almost black and only showing blue at certain angles

Both hands appear old and consistent with the period (not modern or painted).
My question is specifically about what would be most typical / most likely as original delivery for a civil 27 CHRO 12 around 1942.

• Would Omega more commonly fit a black sweep to keep a uniform set?
• Or is a dark heat-blued sweep also a plausible original configuration at that time?

I’m not asking whether heat-blued hands existed in general (I know they did), but rather which choice best fits this specific configuration and year.




Thanks in advance.