In article , says...
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Doesn't work. I had three blackthorn splinters which kept some warts going
for a couple of years.

In desperation a couple of months bak I opened them up with a bloody
scalpel, (one of my aeromodelling sort) and eventually dug out two dust
specks of something black.


I've had that with bits of swarf - I've found that if you can gently pry
the warty bit away from the surrounding skin for a few days it will
eventually stand out enough to rip it out by the root with tweezers.
Painful and bloody but it does the job.