Responsible Metal Detecting

A talk to AiM by Jim Mather

Jim Mather
Jim Mather

The combination of archaeology and metal detecting has been a topic of hot debate. By now, however, only the most fundamentalist archaeologist could fail to appreciate the part that metal detecting can play and ignore the spectacular results it has achieved.

On 20th October Jim Mather spoke to AiM on how metal detecting can responsibly be practised to the benefit both of the enthusiast and archaeology. Jim has been a detectorist for 20 years and, in that time, his finds have been recorded with the Celtic Coin Index, the British Numismatic Society, the Ashmolean and Reading Museums, and the Portable Antiquities Scheme (PAS). He has undertaken archaeological training and, through his reading and membership of detecting bodies, has managed to become well informed and responsible in the pursuit of his hobby.

We learnt that there are approximately 30,000 detectorists in the UK and that there are two main advisory bodies, viz. the National Council for Metal Detecting and the Federation of Independent Detectorists. The principal legislation governing their activities is the Treasure Act implemented in 1997. Two specialist magazines, The Searcher and Treasure Hunting, also cater for followers of this absorbing hobby.

Roman Fibula Broach
Roman Fibula Broach

The Portable Antiquities Scheme (PAS) is a Department for Culture, Media and Sport funded project to encourage the voluntary recording of archaeological objects found by members of the public in England and Wales (a voluntary recording scheme has been operating since 1997). We were urged to have a look at the Portable Antiquities Scheme website at, which includes a database recording nearly 750,000 finds. According to the PAS Annual Report in 2007, 84 % of items on their database have been found by metal detecting with only .02% discovered by archaeology. There are 37 Finds Liaison Officers in England and Wales and 161 out of 170 metal detecting clubs have contacts with these FLOs.

Hobbyists need the permission of the landowners/farmers/councils to pursue their metal detecting. Jim advocated the advisability of entering into signed contracts, which divided the value of any objects discovered on a 50:50 basis between the two parties. We were introduced to the kit involved, of which the principal item, the metal detector, might cost anything up to £3,000. Jim said that his favourite location was ploughed arable land. Detecting is only accurate up to a depth of about 9 inches below the surface. The more sophisticated detectors can discriminate between iron objects, silver foil, aluminium ring pulls, etc. Desirable objects to find, be they coins or artefacts, would be gold and silver, naturally, as well as copper, bronze and lead. Metal finds might range from the Bronze Age to contemporary in time. In his experience, Jim said he averaged about 12 signal reactions, with one coin found, per hour in the field. Eye contact alone could also lead to finds of worked flints, pottery, tiles, clay pipes and glass. The most frequently found items are post-medieval and Georgian, with a greater number of artefacts as compared to coin discoveries. The audience was impressed by the number, quality and variety of his finds which Jim then illustrated in his presentation and also passed around for handling.

The inscription reads Knitt in one by Christ alone*
The inscription reads Knitt in one by Christ alone*

Finds recording is vital for the archaeological record. This might be undertaken through PAS, at local museums, the Ashmolean and Reading in his case, which offer finds identifications sessions, and the Celtic Coin Index which is maintained by Oxford University’s Department of Archaeology – see Additionally, contact would be made with the appropriate county Finds Liaison Officers. If finds are discovered of particular value then matters such as maintaining discretion to safeguard the location and press interest come into play.

The presenter also addressed matters of the law, including obtaining the necessary permission from landowners; theft and trespass, and the avoidance of scheduled sites. Detecting at scheduled monuments is strictly forbidden unless permission has been obtained from English Heritage or Cadw in Wales. These restrictions also apply on National Trust land and at SSSIs – sites of special scientific interest.

We were guided through the main provisions of the Treasure Act. A find must be reported to a Coroner within 14 days of discovery in the following circumstances: any artefact over 300 years old which has 10% or more of gold or silver; more than one gold or silver coin which is more than 300 years old; any hoard of 10 or more coins where the gold/silver content is less than 10%. Such stipulated categories of finds might be subject to retention and valuation by the Treasure Evaluation Committee – in which case the finder and landowner would receive this assessed sum – or returned.

The audience was impressed by the wealth of knowledge and experience that our speaker shared with us. He advocated interest closer liaison between archaeological groups, metal detectorists, and farmers/landowners in recording the rich heritage which this increasingly popular hobby is discovering.

There is a relevant page to be found on the BBC website, which also covers many of these issues at

By Jeff Griffiths

* 1650 -1680. Likely religious or Civil War connections, rather than amatory. Ring found prior to Treasure Act implementation

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