Introduction
Avocational metal detecting remains a highly controversial topic among professional archaeologists and heritage conservationists (Deckers et al., 2016; 2018; Ferguson, 2016; Barford, 2020), with policies varying widely across countries and regions. According to art. 3(iii) of the European Convention on the Protection of the Archaeological Heritage (Revised), or Valletta Treaty, the use of ‘metal detectors and any other detection equipment or process for archaeological investigation’ shall be subject to specific prior authorisation, whenever foreseen by the domestic law of the State (Council of Europe, 1992a). Several European countries have introduced according license schemes (Carnap-Bornheim et al., 2015). The explanatory report of the Valletta Treaty clarifies that ‘the phrase “any other detection equipment” is intended to cover equipment used for a similar purpose...


