Hi Eva...
Older, unmarked pieces like this can be hard to identify, but this one does have some distinctive characteristics. Not everyone seems to visit the "Introductions" forum. You might have better luck posting your photos in the "New Collector's Corner" forum.
When re-posting, give some idea as to the size. The 100 on the lid won't mean much to anyone pertaining to size. Most lids will have a size marking of 7, 8, 9, 10, 11, etc.... 100 would make it the size of a trash can lid. I'm sure on yours, it's some kind of part number and not a size number.
Depending on how big this pot is, the bail wire looks VERY thick. The bail ears (That the wire hooks onto) are very distinctive. The Line under the lid, and under the pot that looks like a defect, is actually a leftover from the way they were cast. That method hasn't been used in a LONG time. Meaning your pot/lid is pretty old.
Oh, and Welcome!! :icon_thumbsup: