Archaeologists exploring northeast Wales have found a mysterious cache of Bronze Age stone tools that are 'unlike anything ever seen before'.

The strange collection was discovered at the bottom of an ancient stream in the Clwydian Range.

The team believes that the tools were deposited deliberately around 4,500 years ago in some sort of ceremony, although the nature of this remains a mystery.

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Archaeologists exploring northeast Wales have found a mysterious cache of Bronze Age stone tools. The strange collection was discovered at the bottom of a stream in the Clwydian Range

THE TOOLS The tools, which vary in size from two inches (50 millimetres) to 8.6 inches (220 millimetres), were made from limestone found locally, according to the researchers. Mr Brooks said: 'They are rough slabs of the limestone, which have been shaped to produce one pointed end. 'But they all have this characteristic point at one end, which has then been battered - you've got pitting and distinctive damage on the end, so they've been heavily used.' While the researchers are unsure what the tools were used for, they believe they may have been used for chipping designs onto rocks. Mr Brooks said: 'One of the things that you do get in the Bronze Age is the decoration of natural boulders and rock faces, producing things like cut marks and rings and suchlike. 'The point on these things would be about the right sort of size for pecking that sort of design.' Advertisement

Researchers from the Clwydian Range Archaeological Group discovered around 20 triangular stone hand tools while exploring the series of hills in July and August.

Speaking to Live Science, Mr Ian Brooks, one of the archaeologists who worked on the study, said: 'I've not seen anything like them before, and I've talked to a number of colleagues who've never seen anything like them.'

The tools, which vary in size from two inches (50 millimetres) to 8.6 inches (220 millimetres), were made from limestone found locally, according to the researchers.

Mr Brooks said: 'They are rough slabs of the limestone, which have been shaped to produce one pointed end.

'But they all have this characteristic point at one end, which has then been battered - you've got pitting and distinctive damage on the end, so they've been heavily used.'

While the researchers are unsure what the tools were used for, they believe they may have been used for chipping designs onto rocks.

The tools, which vary in size from 2 inches (50 millimetres) to 8.6 inches (220 millimetres), were made from limestone found locally, according to the researchers

Mr Brooks said: 'One of the things that you do get in the Bronze Age is the decoration of natural boulders and rock faces, producing things like cut marks and rings and suchlike.

'The point on these things would be about the right sort of size for pecking that sort of design.'

The tools were found on a plateau northeast of the Moel Arthur hill fort – one of six hill forts in the Clwydian Range thought to have been built around 800 BC.

While the researchers are unsure what the tools were used for, they believe they may have been used for chipping designs onto rocks

But carbon dating of the stones from an archaeological feature near the site, known as a 'burnt mound' suggests that the tools could be more than 1,000 years older than the hill fort itself, according to the researchers.

A burnt mound is a feature where stones were heated in a fire before being used to heat water – which could have been used for cooking or even for brewing beer.

The researchers believe that the tools and the activity at the burnt mound were probably associated with a range of Bronze Age activities at the site.

The researchers believe that the tools and the activity at the burnt mound were probably associated with a range of Bronze Age activities at the site

The tools are rough slabs of the limestone, which have been shaped to produce one pointed end. They all have this characteristic point at one end suggesting they had been heavily used

Surveys by the researchers in 2011 and 2012 also revealed that there may have been several roundhouses at the site.

Inhabitants of these roundhouses were likely to be agriculturalists, according to the researchers.

Mr Brooks said: 'The likelihood is that the Clwydian Range was more intensively used than the Vale of Clwyd itself, which is likely to have been wet and nasty, with heavier lands which were less suitable for simple plowing.'

The tools were found on a plateau northeast of the Moel Arthur hill fort – one of six hill forts in the Clwydian Range thought to have been built around 800 BC