Step by Step Instructions
- Acquire 100+ total (don't have to be unique) Trinkets through random looting
- (Optional) Purchase the Salesman skill in the Seer tree for additional 25% profit
- Visit a vendor
- Select 'Sell'
- Use down on the dpad to 'Sell unnecessary items'
To be absolutely clear, the only items counted toward this achievement are listed directly under the word, 'Trinkets' in the Inventory screen. They can be looted in random urns, bags, etc. around the world. You should hit the 100 mark around 10-15hrs of play time, provided you are looting everything.
Please comment as to why you have downvoted if you do so I can correct the issue.
From user MungBard re: trinkets end-game:
"If, like me, you noticed this late and finished the game with fewer than the necessary trinkets, you can start a new game+ and continue collecting. The new game+ will keep the trinkets you currently have in your inventory. I was able to get the last 20 or so I needed before I ever left Siwa."
From user ResidentialEvil
"for me the urns at military encapments have been respawning."