prehistoric stone ball found

http://phys.org/news/2016-04-archaeologist-bosnia-stone-sphere-massive.html

This is not the first giant prehistoric stone ball found. If these balls were man-made and not natural, why did some prehistoric men go to the effort of making such huge balls? Perhaps they just wanted something a bit more impressive than their own to show off.

Originally posted by humy
http://phys.org/news/2016-04-archaeologist-bosnia-stone-sphere-massive.html

This is not the first giant prehistoric stone ball found. If these balls were man-made and not natural, why did some prehistoric men go to the effort of making such huge balls? Perhaps they just wanted something a bit more impressive than their own to show off.

The article reads like it was not only translated but written by a non-scientist with something to prove.

Secondly, they had high technology, different than ours.

Seriously it isn't that hard to carve a stone ball.

Of course I don't believe for a second that it was made by humans.

Originally posted by twhitehead
The article reads like it was not only translated but written by a non-scientist with something to prove.

Secondly, they had high technology, different than ours.

Seriously it isn't that hard to carve a stone ball.

Of course I don't believe for a second that it was made by humans.

The thing weighs 30 tons, it's not trivial, especially since they won't have had metals to do it with. The telling sentence is the one following yours:

Finally, they knew the power of geometrical shapes, because the sphere is one of the most powerful shapes along with pyramidal and conical shapes.

Assuming this isn't the result of mistranslation the guy appears to believe in leylines and other such pseudoscience. It's not clear what he means by "high-technology" either. In the context of the time or actually compared with ours?

Various geologists have proffered more plausible explanations:

A lecturer at the University of Manchester School of Earth, Atmospheric and Environmental Sciences told MailOnline that the spherical stone may be an example of concretion. This is when a compact mass of rock is formed by the precipitation of natural mineral cement within the spaces between sediment grains. The result is often spherical in shape, with the process forming the famed Koutu boulders in New Zealand.

Experts at the Geological Society, according to MailOnline, said the round shape of the rock could come from spheroidal weathering. This is a type of weathering affecting jointed bedrock. The result is formation of concentric or spherical layers of highly decayed rock.

"He said actually less than half of the ball is uncovered."

Which means that it may not be a ball. It may be the rounded dome of an irregular shape below.

Originally posted by DeepThought
The thing weighs 30 tons,

Does it? That estimate was made because it looks a little brownish and then they assumed it was mostly iron.
But the mass is irrelevant to how easy it would be to carve - only the hardness of the rock and total amount of carving required.
Was stone henge pre-iron age?

it's not trivial, especially since they won't have had metals to do it with.
Not impossible either. It still doesn't point to 'high technology different from ours'.

Experts at the Geological Society, according to MailOnline, said the round shape of the rock could come from spheroidal weathering.
That seems likely to me.
It must also be noted that there is no actual evidence that the rock is a sphere, only about half a sphere is exposed. It could be any shape on the other side.
I have certainly seen lots of rounded rocks, usually due to weathering for the larger ones.

Zimbabwe has mountains that are rounded and plenty of boulders:

http://3lxvd933pgzi5mhrmx219v13h1.wpengine.netdna-cdn.com/media/ZIM-Matopo-NP.jpg
https://bamboobikeride.files.wordpress.com/2012/03/rhodes-grave.jpg

Now if it had looked like this:

https://en.wikipedia.org/wiki/Celtic_art#/media/File:Towriepetrosphere.jpg
dated from 3200–2500 BC

I might be impressed.

Originally posted by twhitehead
Does it? That estimate was made because it looks a little brownish and then they assumed it was mostly iron.
But the mass is irrelevant to how easy it would be to carve - only the hardness of the rock and total amount of carving required.
Was stone henge pre-iron age?

[b]it's not trivial, especially since they won't have had metals to do it with. ...[text shortened]... com/media/ZIM-Matopo-NP.jpg
https://bamboobikeride.files.wordpress.com/2012/03/rhodes-grave.jpg[/b]

No the overall size matters, it makes it much more unwieldy. Stone henge does not involve spheres it involves rectangular stones, which is a lot easier to arrange. The ancient Egyptians used water and sand to cut through rock to make their stone bricks, possibly the builders of stone henge did something similar. That's fine if you want a rectangle, but a pain if you want what is nearly a sphere.

Originally posted by DeepThought
No the overall size matters, it makes it much more unwieldy.

Size yes, weight no. And its only 'unwieldly' if it needs to be moved. As for size the only real difference is how long it takes to carve it (or how many people you need to do the job). Doubling the size doesn't mean more technology, it means more time or more people.

Stone henge does not involve spheres it involves rectangular stones, which is a lot easier to arrange.
Yet they were cut and transported over vast distances. It seems to me that that would be far harder than carving up one sphere in place.

The ancient Egyptians used water and sand to cut through rock to make their stone bricks, possibly the builders of stone henge did something similar. That's fine if you want a rectangle, but a pain if you want what is nearly a sphere.
Depending on the strength of the stone, it really isn't that hard. I agree that metal does help, but it is not essential.

Of course Egyptians did have metals and did some pretty intricate carving.

Originally posted by twhitehead
Size yes, weight no. And its only 'unwieldly' if it needs to be moved. As for size the only real difference is how long it takes to carve it (or how many people you need to do the job). Doubling the size doesn't mean more technology, it means more time or more people.

[b]Stone henge does not involve spheres it involves rectangular stones, which is a lo ...[text shortened]... of the stone, it really isn't that hard. I agree that metal does help, but it is not essential.

To make a sphere you have to rotate the block. The weight matters, something light and large is easier to deal with than something relatively small but heavy, for one thing you need to worry about it shifting position and killing one of your masons.

Originally posted by DeepThought
To make a sphere you have to rotate the block.

No you don't.

The weight matters, something light and large is easier to deal with than something relatively small but heavy, for one thing you need to worry about it shifting position and killing one of your masons.
Still, its not a major technological innovation to work on a larger heavier stone. Moving it to a particular location, maybe. But then the stone in question does not appear to be sited in an ancient city square. That is one of the reasons I don't think it is man made.

Originally posted by twhitehead
No you don't.

[b]The weight matters, something light and large is easier to deal with than something relatively small but heavy, for one thing you need to worry about it shifting position and killing one of your masons.
Still, its not a major technological innovation to work on a larger heavier stone. Moving it to a particular location, maybe. But ...[text shortened]... to be sited in an ancient city square. That is one of the reasons I don't think it is man made.[/b]

There are clear spheres in Costa Rica:

https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=stone%20balls%20in%20costa%20rica

Originally posted by humy
http://phys.org/news/2016-04-archaeologist-bosnia-stone-sphere-massive.html

This is not the first giant prehistoric stone ball found. If these balls were man-made and not natural, why did some prehistoric men go to the effort of making such huge balls? Perhaps they just wanted something a bit more impressive than their own to show off.

After trying to play football with the stone balls, prehistoric man quickly abandoned them 😵

Originally posted by humy
[b]http://phys.org/news/2016-04-archaeologist-bosnia-stone-sphere-massive.html

...why did some prehistoric men go to the effort ...

They saw something in the rock, from their imagination, and just started chipping away the stone that didn't belong. The group must have been doing well at surviving, and had time to kill.

Originally posted by apathist
They saw something in the rock, from their imagination, and just started chipping away the stone that didn't belong. The group must have been doing well at surviving, and had time to kill.

Rather than Neandertals?