
the shards of metal you talk about are not an issue for a start hawks only get slithers of venison , my eyesight is good enough to see a foreign body in the meat.
If a lump on metal of any type was eaten, by some chance of me feeding my hawk blindfolded then the hawk would regurgitate the lump of metal the same as bits off bone on feather / fur.
This issue is smaller dust particles off lead that would be digested as it is TOXIC

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The copper dust if any is NOT toxic.
You are getting hung up on shards of mental getting into the gut- shards of metal won’t get into a gut of a hawk as they empty crop every day with non digestible items- lead dust is digestible and TOXIC
I am starting to think that you are just playing to fool so you have someone to talk to