On a blog near you, metal detecting Micheal carelessly mentions:
I used sandpaper in coins.. I suspect that there were more than a few quite scarce ones too…Rather than a concern with artefact hunting best practice (what the PAS is supposed to be teaching heritage-grabbing oiks), this individual is apparently only concerned about the loss in resale value of the items.
Other detectorists used rock tumblers to 'clean' the historical metal artefacts they dig up, here's a range being sold as 'cleaning equipment' by a south coast dealer. Needless to say, museum professionals do not use such amateurish methods as UK metal detectorists.
When millions of artefacts are being dug up an 'curated' (I use the term loosely) in scattered ephemeral personal collections in the UK (and worldwide), it is a matter for concern that we so often read material on the forums and blogs that suggests that very few of thee collectors owning such assemblages have any idea at all how to look after the material in their care. This is no way to treat the archaeological heritage.