Artificial patination and bronze disease

[Aleph]

There seems to be a great number of artificially patinated coins on the market in recent years.  While I am not opposed in theory so long as it is non destructive and tastefully done, the problem I am encountering is what happens to this patina when the coin is treated for bronze disease.  What I am finding is that following prolonged treatment in distilled water and dilute sodium sesquicarbonate (just enough to ensure the solution is not acidic) at room temperature is bringing out a splotchy green patina.  Should I try to repatinate the coins?  Should I try and push this treatment longer to complete the removal of the new patina?  Any suggestions?

I see this topic was also briefly mentioned in this past thread
https://www.forumancientcoins.com/board/index.php?topic=56295.msg350027#msg350027

Thanks!

[Ron C2]

The problem with artificially patinated coins, in many cases, is real and stable patina is removed before it's applied.  Often this is done to get something like a faked desert patina.

I prefer to avoid such coins altogether if I suspect any patina manipulation.

For BD in general, see here for some good tips:

https://www.forumancientcoins.com/numiswiki/view.asp?key=bronze%20disease