Old coins identified by numerical data (including old sovereign) (7)
I believe the answer is:
staters
'old coins identified' is the definition.
I know nothing about this answer so I can't judge whether this works.
'numerical data including old sovereign' is the wordplay.
'numerical data' becomes 'stats' (statistics).
'including' means one lot of letters goes inside another.
'old sovereign' becomes 'ER' (Elizabeth Regina, ie Queen Elizabeth).
'stats' enclosing 'er' is 'STATERS'.
'by' is the link.
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