This is not a difficult quest on its own, however it is somewhat tedious.
Everyone in the group will need access to the lower Vergalid area (Flawless Indicolite Shard). This can easily take many hours to get 6 shards to drop.
Once you click through you will need to make your way to the Void area which involves having a fairly good dps group to clear mobs and keep ahead of the respawn (our group had Qvic/Txevu geared toons) and included rogue, pally, chanter, cleric, tank, ranger. Mobs come in 2's and 3's and hit around 1500. The area round the void itself has 75+ level mobs and is a fun "crawl". The blackvein ore is very common and drops off almost every mob.
Most of the named in the area drop loot which is below the level of the group required to kill the mobs as is typical. The reward is also sub par for the level of group required to get it. We had very few difficulties, but killed fairly quickly.
You will need the quest ahead of looting the ore. Handing samples back to Fentier without the quest update is of no use.
If I was rating the quest, I would have to say 1 out of 5.