Sticky Film On Silver Quarter, Impervious To Hot Water And Acetone.

Brandmeister said on 8/21/2025 "I am still new to cleaning and conserving coins. Mostly what I know is BadThad's polarity ladder of Distilled Water > Acetone > Xylene > Sodium Sesquicarbonate > Verdicare, as demonstrated by DOCC. But the only coin-safe solvents I currently own are water and acetone.

Is there a coin conservation site somewhere that discusses what solvents are effective against what deposits?"

I would like to know where the demonstration by DOCC is located-is there a link to a post? The only parts of BadThad's polarity ladder I've seen so far are your first three and the last. Where was the Sodium Sesquicarbonate discussed?

And, a cheap source of mostly Sodium Sesquicarbonate is Savogran's Phosphate Free TSP-PF. It contains some EDTA which will bind with any soluble metals which come off of the coins surface and Sodium metasilicate which I think is a water wetter, but that is trusting my memory, which can be dangerous.

Savogran is now owned by the Sunnyside Company.

Edit: My memory is wrong. According to Wikipedia again, Sodium metasilicate is used in soaps and detergents "as an emulsifying and suspension agent."

That means it will break up oils and remove them from surfaces. But it will also cause glass to become cloudy. And we've been told to use glass containers for cleaning. Maybe best not to use this and get pure Sodium sesquicarbonate.

I had used 99% isopropyl alcohol on a 'sticky' covered coin, and most of the gunk came off but not all. I use 99% isopropyl alcohol when working on and cleaning fiber optic cables. It is virtually free of any foreign debris and water to stain a coin (of to mar up a fiber end)

Worthy of a bookmark. Thank you for sharing.