Hello Jan,
As stated so many times by now, these "full red" diamonds are not original to the HJ knifes:
I have seen hundreds of late HJ's, dated 1940, 1941 and 1942 (the last year of HJ knife production) by all of the makers. Never a knife that was in great condition had a "full red" diamond.
Unlike for other unusual features (like for instance the late period plastic hanger which is typical for Kaldenbach's, RZM M7/72 marked HJ knifes), not a single maker can be identified for having used the full red diamond: these fake inlaids end up on all kinds of knifes by different makers, most often on pieces that are already in bad shape.
Some owners of "full red" diamond HJ knifes may which to believe what ever they want... but here, at the HJ forum of GDC, we are strict when it comes to authentication: we need proof!
And believe me, when it comes to "full red" diamond HJ knifes, there is not any to be found!
Few people seem to know that many HJ knifes with a correct, "dotted red" diamond also have a replacement diamond. That is because a lot of the knifes got denazified after the war. So in the best case, the diamond of a HJ pin was used as a replacement. That is why sometimes the diamond is too large for the cutout: early knifes had a smaller diamond, which is touch to find in the "pin" version...
Many bad condition HJ knifes however ended up with the "full red" diamond for obvious reasons...
Best regards,
Herman
