Uncommon Monster Part Gift Clarification Needed

[Von Pink]

Been trying to find out what is what and it's frustrating. Are they referring to the monster or the part? Does a severed tail count because it's less common of a drop or are we talking something like ogre parts because the monster is rarer? Been trying to figure it out for the weapon merchant in the Battahl capital and his responses are always dismissive no matter what monster part I give. I gave him a dragon scale just to see and the only way it could seem like I offended him more would be if he spit at me. Is it just that NPC is a complete ♥♥♥♥♥♥♥♥ and I'm being thrown off by the responses or am I missing something else?

nvm. I found out the bunch of flowers gift works on everyone regardless of their gift preferences making trying to figure this out pointless

[ChyHart]

He's so rude, sometimes like when i gave him a Rugged Bone , and oily slime (rare monster drop) He said "that's more than my life's worth" Which is an approval. But he's also said ""What a bother." for the oily slime, he's kind wishy washy. So far the Scrap Iron has had many positive responses. I think this NPC is just a grump.

[Grr. [SG CMD] Majah Lazah]

flowers.
Malleating elixir