Because it was carved with nothing more than stone tools, we know that it may have taken many months, if not years, to produce.
The unstated assumption is that metal tools would have speeded the process. That's funny. As one who works daily cutting and carving stones, let me clear up some confusion here. Even the hardest modern tool steel is much softer than the mineral jadeite (one of two minerals properly called "jade," the other being nephrite.) Both would defy and destroy metal carving tools.
Jadeite (hardness 6.5 to 7) was carved by abrading it with other stones known to be of greater hardness. That's essentially the same way such carving is done today. I use metal wheels and carving points with diamond, the hardest known stone, imbedded or sintered into them. It's the diamond, not the metal, that does the cutting. Ancient carvers used much the same technique with the sands of minerals like corundum (hardness 9) as an abrasive. This is the "quick tour," it's much more complex, but those are the basic ideas.
Do you stone carve as a business? Any website?
as a small sidebar to your nice post, those walls made of odd-shaped (often quite large) stones, without mortar, and with a fit so tight that a blade can't be shoved in the crack, were made in a similar way -- by sliding the stones back and forth against each other, wearing each other smooth until they fit. Or so the story goes. :')
Sorry to be so ignorant about this, but if the diamond is the hardest known stone, what stone is/was used to cut diamonds?