Not sure about "grapefruit-sized" when compared to the hand holding the object in the picture. Assuming it's the one they are writing about.
I'd say it's closer to the size of a lime.
Unless that person has a uniquely large hand of course.
Really interesting find though, never heard of these artefacts before.
Quite. I suspect the narrator might have confused grapefruit with satsuma - easy to do if you ignore size and colour ... morphology and a few other things but all citrus so all good.
Really interesting find though, never heard of these artefacts before.