This was in the Museum of Anthropology, in Mexico City.
Notice the bit chunky, utilitarian looking blades at the top, and compare them to the long, really skinny ones at the bottom.
I immediately remembered this paragraph, from "Shelling Out -- The Origins of Money" by Nick Szabo (https://nakamotoinstitute.org/library/shelling-out/).
Native American money took many forms besides shells. Furs, teeth, and a variety of other objects with properties we will discuss below were also commonly used as media of exchange. 12,000 years ago, in what is now Washington state, the Clovis people developed some marvelously long chert blades. The only problem -- they break far too easily. They were useless for cutting. The flints were being made "for the sheer enjoyment" -- or for some other purpose that had nothing to do with cutting. [G01] As we shall see, this seeming frivolity was, quite likely, actually very important to their survival.
I think these blades are similar. They're so thin as to be useless. HOWEVER, I'm sure they take a lot of very painstaking work to create, and I'll bet it's very, very easy to break one in the process of making it.
So - proof of work. Proto money.
Cool, huh? I wonder what archeologists think about these kind of finds.