Regarding the "curved knife" -- I have always seen that referred to as a "Green River Knife," the primary tool of the skinner/hunter/trapper of the day. The design stuck because, simply, it worked. They were manufactured in their untold thousands/millions and used across the continent. Each one has tales to tell, and is worth keeping.

There are many other made-for-purpose antique knives. I have a couple that were hand-made by my grandfather, from old circular saw blades (the kind that were six feet across). One is a genuine pig-sticker, used to slaughter hogs. The other is a turkey knife, which was used to slaughter turkeys; the method of its use is ingenious and likely quite humane, though a bit freaky.