IT was a routine day working in the Ochil hills of Perthshire for gardener Joseph Sheppard, tilling the soil where the next generation of conifers would one day take root.

But when he stepped back to admire his handiwork, he found he'd uncovered more than just roots and soil.

Nestled amid one of the furrows he'd dug was an artefact dating back more than 4,000 years to the time when the early inhabitants of Scotland built their great stone circles were across the land.

And just like those monuments, the object - a stone ball carved with six symmetrical panels - is one of a group which has baffled archaeologists since they were first discovered.

Now a fundraising campaign has been launched to save The Sheriffmuir Ball for Perth's museum, with £1,625 needed to fend of bids from rival exhibition spaces. 

The cost is especially high as the ball is one of the best examples ever found - and one of only 49 to bear decoration marks.

The Herald:

Mr Sheppard with his find 

It could so easily have gone unnoticed, but luckily Mr Sheppard recognised it for what it was, even if its appearance was totally unexpected.

He said: "It was just poking out of one of the furrows made by the digger as it went past. If it had been a couple of inches closer it would have been crushed.

"I knew exactly what it was because I have an interest in that period of history. I'd been hoping to find something like it all my life.

"I was just delighted to make the find. I was the only one on the job so I couldn't tell anyone straight away - I just had to jump around on my own."

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Found almost exclusively in Scotland, around 520 examples of the carved stone balls have been discovered in various places, mostly in the North East around Aberdeenshire and Orkney.

Mr Sheppard's find is one of the most southerly even discovered, and although there are many theories about what the balls were intended for, their purpose remains lost to the mists of time.

At various times they have been said to be weapons, weights for fishing nets, or even the ballbearings used to roll mighty stone circles into place. Other suggestions for their creation include elaborate game pieces - each is about the size of a cricket ball - or showpieces crafted by ancient artists to display their skills.

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The ball was carved around the time the Ring of Brodgar was built

Among the finest found is the 'Towie ball', uncovered on Glaschul Hill, Aberdeenshire, in 1860, which is carved with a design which is echoed in the Neolithic tomb at Newgrange in Ireland.

Mr Sheppard, of Edinburgh, said that he had made occasionally found historic items before, such as fragments of clay pipes and neolithic flints.

But he had never dreamed he would one day uncover anything as significant as the Sheriffmuir Ball.

"When I dug it out it looked as though it had just been made yesterday. The quality of the carving is remarkable, I have worked with stone a lot over the years and it would be hard to recreate even with modern tools.

"It is my belief that they were like a masons show piece made by the people that understood the sacred geometry used to build the stone circles and to predict the movement of the planets.

"The lines I feel refer to planetary moments such as eclipses or full moons that the keeper may have witnessed," he said.

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As well as satisfaction from uncovering the ancient stone, he will be in line for a healthy reward once the dust has settled. Finds such as this are covered by Treasure Trove legislation, which dictates that the finder is given some of the monetary value of any artefact uncovered once it is given to a museum.

But Mr Sheppard is more interested in seeing the ball given a proper home, and is backing the campaign to have it kept in Perth.

He said: "It was hard to part with, but I'm really glad it's going to go on show in Perth Museum. That's where it belongs."

Anyone who has handled one of the carved balls remarks on how well they fit in the palm of the hand, although each is surprisingly heavy given its size.

Dr Hugh Anderson-Whymark, Curator of Prehistory at National Museums Scotland (NMS) has examined the Sheriffmuir Ball, and prepared a detailed 3D model for posterity.

The Herald:

The Towie Ball

Dr Anderson-Whymark said that analysis showed that the object had a long history before it ended up in the ground, and likely many different owners.

This suggests it played an important part in the lives of many people, perhaps a family of neolithic farmers.

The curator said: "This is an amazing example of one of these balls. Sometimes they are damaged when they turn up, or have been worn down by the elements, but this one is completely intact."

He added: "What is interesting about these objects is there appears to have been a sequence of manufacture. They take a long time to shape and are added to at different times.

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"If we look at the lines carved on the Sheriffmuir Ball through a microscope, we see that one of the patterns was carved in a different way to the other.

"It's an object which has passed through many hands and has been added to over time, reworking the surface.

"It all adds to the mystery of what they are and why they were made. But the people back then left no written records."