1948 S Jefferson Nickel / Cud + RPM (?)

@mr5, I'm interested to see what others think, but I'm not convinced that is a Cud. Yes it is attached to the rim, but it looks more like it is on top of the coin surface and is a bit ragged in shape.

Spence, interesting observation, but if not a Cud...post-mint damage? I'm anxious to hear.

Not a Cud. Might be a Rim Fin. I don't think it's an rpm. The die scratch you point to under the C is almost vertical, on your coin it's damage going diagonal.

Not sure about either of these, not seeing an RPM, as for the Cud I agree it could be a possible banged up folded Rim Fin, I posted on similar on a Canadian nickel. I'll try and find the photos or link, it kind of looks like there is Shadowing under the potential Cud which makes me think Rim Fin as well but would need a different angle.

Edit; took a little bit to find, I have learned a fair bit since this post lol, but it does look slightly similar but larger then yours

http://goccf.com/t/404538

Damage to the rim/edge is not a mint error, but coin damage.

A retained interior die break is just that, interior. Your piece of outstanding metal is on the rim and therefore is not an RIDB. I am not sure what the large piece of material is on the reverse adjacent to the mm. It is very odd to say the least.

IMHO it looks like a Cud and not a Rim Fin . The elongated part going to the northwest is a little odd but if the main section was indeed a Cud and the die started to chip in that direction that could explain it (unless it turns out to be solder).

For those thinking it is a Rim Fin, isn't a Rim Fin found around the outside perimeter of a coin (where the obverse or reverse die meets the collar die and not in the die gutter)?

An image with the light source from the left might cast light onto the area where the raised metal meets the field and that might offer more clues. right now that area is in the shadows.

Mr5Hole,
Thank you very much for a detailed description of what you were seeing and the images with arrows to easily point us in the right direction. It goes much easier for everyone with threads like yours. (I'm not sure about the legality of the use of the images from a copyrighted online source in your post which is why we usually use links to the web page.)

As for an RPM, your coin doesn't match the markers or MM position for the images provided. The secondary MM appears to be south of the main one (separation on the bottom of the upper curve). The mark below CENTS looks to be a hit (incuse) and it goes a different direction than the die scratches on the VV images.

Thanks again for your excellent post and maybe a clear image with light from the left would be helpful?

I think the last image the OP posted was the ding at K1 on the obverse as pointed out by Bumpkin.

Unfortunately, the OP didn't specify where that ding was, but I'm not seeing anything like it near the extra metal.

I still have hope the OP will get an image with the light source from LIBERTY or thereabouts that might shed light on the edge of the metal bump at the field.