I am doing an ancient stream with rocks and stones and d2 is silent but soil round the edges has iron sounds aplenty so I presume it won’t find coins under some stones which maybe to dense
This hoard on jersey needed the whites hoard hunter to find it
they had lose coins to point them in the right place
https://archaeology.co.uk/articles/news/excavating-jerseys-record-breaking-celtic-coin-hoard.htm