Vitrified Forts ping

That is true of modern flintknappers, and it was spectacularly true of the ancient Maya, et al.

Even artisans who consider themselves to be highly-competent in the wielding of soft hammer thinning, pressure flaking and indirect percussion (punch) techniques cannot escape a sense of awe at the superb skillset required to create something like the above object. And they will readily admit to two truths about such objects:
The same holds true of "showpieces" by master bladesmiths -- past and present...
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IMO, the stone balls and all the rest of these objects are "Badges of Mastery"...