I think obsidian is not good for cutting a shape like this because it's extremely brittle, though you are right that it's far sharper than would even be required.

I really don't know about this subject but from my limited experience, can't you also just make a superficially similar curved cut using a large number of straight cuts at increasing angles? Basically whittling. The edges of the map are pretty irregular, anyway.

[–] SerialExperimentsGay@hexbear.net 14 points 10 hours ago (1 children)

Before the 1800s, the Pawnee mostly used flint tools. Less sharp, but holds an edge better than obsidian. idk if they cut the leather for that map with flint or with a metal blade they traded in, but it seems kinda pointless when the objection is coming from a guy who, unlike pre-Colombian Pawnee, would be miserably trampled to death if he had to hunt bison with flint arrows and without a horse.

[–] Kefla@hexbear.net 9 points 7 hours ago

You could give this loser a gun and his choice of horse, car, or bike and he'd still probably get owned by the bison

[–] DasRav@hexbear.net 22 points 11 hours ago (2 children)

I don't get what the issue is. A flint knife will cut leather just fine.

[–] Johnny_Arson@hexbear.net 13 points 11 hours ago

Even funnier when "geologist" is in his bio lmao

[–] purpleworm@hexbear.net 8 points 11 hours ago (1 children)

Would flint be effective for cutting long curves like this?

[–] DasRav@hexbear.net 14 points 11 hours ago

Flint is hella sharp, so I don't see why not. You don't necessarily need specialized tools to cut a circle, practice makes perfect and native americans had a lot of practice on that front.