How to get just a few more objects for the museum?

[Drachenbauer]

I need just 2 or 3 more objects for the Museum to optain the sewer key.
But for a long while i get only duplicates, when i open geodes or dig in artifact-spots.
In artifact-spots i find really often stuff, that is not for the museum (seeds and naturals)

What else can i do?

 

[HaleyRocks]

I need just 2 or 3 more objects for the Museum to optain the sewer key.
But for a long while i get only duplicates, when i open geodes or dig in artifact-spots.
In artifact-spots i find really often stuff, that is not for the museum (seeds and naturals)

What else can i do?

Visit the stardew valley wiki and check up on Artifacts and Minerals. See what you're missing, where those have a chance to appear and go hunting.

1 Dig with hoe. Enchanting it with "Archeology", helps a little bit.
2 Craft treasure totems. Those are a real asset.
3 Trade Omni-Geodes for Artifact-Troves at Desert Merchant and/or dig for artifact troves at artifact spots, at Ginger Island.

 

[Drachenbauer]

I dig alot with hoe, but i don't know how to enchant it.
I think, i don't have unlocked that feature, and i also don't have unlocked traveling to ginger island

 

[Bawby]

I dig alot with hoe, but i don't know how to enchant it.
I think, i don't have unlocked that feature, and i also don't have unlocked traveling to ginger island

Okay, so island is out and SC is out...
The only advice I can give that's not repeating @HaleyRocks is fish for treasure. That and make sure what you have already doesn't need to go to Gunther. Sounds silly, but one save I went forever not completing the collection just to find out what I was missing was a quartz. Something I had hundreds of in a chest.