Remove Lead (i.e. Pb) marks from an enamel bathtub?????

Would anyone have any suggestions on how to remove lead rub marks on an enamel surface. There were lead weights on the inside of my shower liner
that have created marks over time when they flipped around due to the billowing of the liner. Nothing I have used has worked.
Tried and Failed:
1) Dremel Moto tool with felt polishing wheel 2) Comet 3) Gojo abrasive hand cleaner
I didn't rub too hard with any of the solutions for fear of damaging the surface.
Ideas: 1) heat gun + abrasive 2) Dremel felt wheel + abrasive 3) Chemical???
Apart from using aqua regia or hydrofluoric acid, is there anything that would attack the lead without destroying the enamel?
Any ideas would be much appreciated.
Notes: It is a metal tub with a, presumably, enamel surface.
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Chlorine bleach. Be cautious of chlorine gas from other reactions.
IIRC, the lead turns into lead chloride and is transported down the drain.
Martin
Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder
NYC Doc wrote:

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If this doesn't work - then carefully try battery acid. If you have a motorbike then maybe some is left over for the experiment. Remember it will eat most everything it touches...
Martin
Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder
Martin H. Eastburn wrote:

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wrote:

Get ye to a sporting goods store...a -real- sporting goods store that sells shooting supplies. You can purchase commercial lead removing chemicals that shooters use to de-lead their barrels.
--
Harry Andreas
Engineering raconteur
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Borax (20 mule team brand, etc) is excellent for cleaning and scrubbing enamel, porcelain, etc.
-Tom

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