The "exceptional" part is literally a quote from the top expert of preservation for the region.
> The sword and the burial still need to be examined, said Conservator General Mathias Pfeil, head of the Bavarian State Office for the Preservation of Monuments. “But we can already say: the state of preservation is exceptional!”
> The sword and the burial still need to be examined, said Conservator General Mathias Pfeil, head of the Bavarian State Office for the Preservation of Monuments. “But we can already say: the state of preservation is exceptional!”
This article has more photos and compared to the sources mentioned here does seem much better preserved. The entire sword doesn't even look corroded https://www.welt.de/geschichte/article245860994/Archaeologie...