What are they? Not even Dulfy seems to have them.
Judging by the patch notes you just swap out the vial for bloodstone dust and there you go.
Pretty sure they are just the current back pieces (minus the 2 former magic find items) but using blood stone dust instead of mist essence.
Not affiliated with ArenaNet or NCSOFT. No support is provided.
All assets, page layout, visual style belong to ArenaNet and are used solely to replicate the original design and preserve the original look and feel.
Contact /u/e-scrape-artist on reddit if you encounter a bug.