Nautilus shell? (Field Research community centre bundle)

I'm trying to complete the Field Research bundle of the community centre and I'm only missing the Nautilus Shell. I've gotten two Nautilus Shells before, but both times, it wasn't the "right" Nautilus Shell apparently as I couldn't put it in the bundle. I can't seem to find the right one anywhere. I've tried looking online, but I only can find a SINGLE reference to Nautilus Shell instead of multiple, which confuses me.

I'll add some images for clarification

The one I've found:

The one I need :

I can't seem to find any info on the one I need, and it makes it difficult to search as they have the same name. Is the one I need also an artifact? Where is it found?

Solution 1:

According to the official Stardew Valley wiki:

Note: The bundle wants the shell found by foraging from the beach in the Winter, NOT the one from the mines/geodes.

I can't find anything that mentions what the drop rate is, but searching on days where the Fortune Teller says you have a little extra luck may help!

Solution 2:

If your friendship level is high enough, Demetrius can also gift you a shell in the mail, it was how I managed to complete the bundle in Fall. (However, gifting seems random, as one time, Pam gifted me cooking items but I restarted that day and had the same letter but it contained a battery)