At the end of The Artisan's Work quest (recover 16 groundspawns), when you hail Lebounde he responds like so:
06/23/16 11:38:15 PM You say, 'Hail, Lebounde ab Dolmen'
06/23/16 11:38:16 PM Lebounde ab Dolmen says 'Ah, Sirenea! Good t' see yeh. Back fer more [work]?'
06/23/16 11:38:17 PM Lebounde ab Dolmen says 'Yeh've proven t' be a quite the explorer in recoverin' meh equipment. If yeh can prove t' be a true craftsman then meh finest prize is yer's.'
06/23/16 11:38:17 PM Lebounde ab Dolmen says 'I'd recommend yeh read through the 10 chapters of Liber Brassica Felix when yeh get the chance.'
06/23/16 11:38:17 PM Lebounde ab Dolmen says 'I suggest yeh have a chat with Aid Grimel out in New Tanaan.'
06/23/16 11:38:17 PM Lebounde ab Dolmen says 'Yeh should speak t' Eron Nurwistle next time yeh head through Dragonscale Hills.'
Say "work" to get any (TS) Supplies quest which you qualify for (you must have max skill and a max evolved trophy in that tradeskill to qualify. 15% mod items from Luclin etc. don't count).
After turning in all 12 seals, the next step appears:
[Sun Jul 10 20:28:35 2016] You say, 'Hail, Lebounde ab Dolmen'
[Sun Jul 10 20:28:35 2016] Lebounde ab Dolmen nods approvingly, 'Yeh proven t' be a true craftsman, very well. Head back t' meh house, just south of Shanis' place. On meh table yeh'll find a small box. If luck's on yer side and yeh got a steady hand yeh should be able t' meld t'gether yer Solstice Earring, Taldarius' Signet, and Eron's Jewelry. Head back t' meh after yeh succeed.' He pauses, 'Well... If yeh succeed.'
Go to his house, click the door and you'll port inside. Click the little box on the table:
[Sun Jul 10 20:31:35 2016] You dig through the various objects on the artisan's table and recover a small ornate box.
It's a 3 slot box which you combine:
Earring of the Solstice (NOT Xanthe's Earring of Nature)
Signet of Might OR Signet of the Arcane (caster & melee reward of Aid Grimel PoP super TS quest)
Eron's Jewelry (caster or melee version)
This combine is failable, but when you fail you get the quest items back. AFAIK you don't have to do this combine in Halas, and you don't have to be in his room. Once you leave the room you cannot get back in.
[Sun Jul 10 20:42:12 2016] You have fashioned the items together to create an unexpected product: Expensive Mistake
The result of this combine is Expensive Mistake. This is the item you are supposed to get and can finish the quest with. Hand it in to Lebounde:
[Sun Jul 10 20:42:38 2016] Lebounde ab Dolmen holds up the mangled mass of gems and leaves that was once your prized treasures. He inspects the mass carefully and then looks at you, then looks back at it, then back at you. He breathes heavily and begins chuckling before looking back at the mass again and erupting in uproarious laughter. He places the tangled mess in his pocket and wipes a tear from his eye before calming himself enough to speak, 'My god, Sirenea. What a mess yeh made! Truth be told, I dinnae really expect anyone else t' be able t' make use of that finicky little box. Yeh gave it yer best try and I respect yeh for it, fine enough work t' earn somethin' at least. Maybe with this yeh be less likely to mess up yer next project.'
[Sun Jul 10 20:42:38 2016] You have been given: Artisan's Prize
The first player on each server to complete gets the following serverwide message:
[Sun Jul 10 20:42:38 2016] <SYSTEMWIDE_MESSAGE>:A proclamation rings out over the Frigid Plains, 'Halas wishes all across the land to join us in congratulating, Sirenea, for being the first to earn the Artisan's Prize.'