Apparently there is wrong quest letter
I found Queen bee letter and it said I must gather 30 gold dust.
So I use my craftman to collect gold dust outside the zaid.
But after 30, I delivered them to Pet trainer and she reject it.
Im frustated and later need more slot inventory so I drop that letter.

Then when I reach higher level and hunting on east red soil, I found a loot named "... gold" or whatever probably the right item.
But I swear the letter said it gold dust.
Can somebody clarify this ?