John Wyatt paid £50 for the gardening gear but the tiny stone alone could fetch a whopping £10,000!
The 32-year-old started cleaning the stone which revealed the 21in by 15in Anglo Saxon carving that featured a cross on one side and a bird on the other.
Speaking about his find, the Chester-based chap was quoted in the Daily Mirror saying: "It was lucky I was looking."
The pricy piece is set to go on sale at auction this Friday in Dorset.
Suddenly heading to our local garden centre seems a lot more appealing…
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