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 Replies: 29 / Views: 2,531 |
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Bedrock of the Community
United States
19935 Posts |
Quote:
There is also the matter of how the coin is laid while submerged. If laid flat, it will need to be flipped. I have a clear 4-oz glass bottle with a tight sealing cap. I toss the coin in, dump in my solvent, swirl it around a bit and let it stand. Every few hours or so I'll flip it just by jiggling the bottle. Again, don't over think it here unless your coin is already falling apart. LOL Just monitor your solvent color, replenish as needed if it's getting saturated. No need to stand the coin on edge, you'll expose both sides plenty enough with some periodic swirling. The whole key to this is watching your solvent. You'll see it getting darker or changing colors if the solvent is working. I've seen chunks just fall off too. After soaking in any solvent be sure to give the coin a fresh rinse after you remove it. I like 100% ACS grade or better IPA or acetone. |
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Valued Member
 Italy
284 Posts |
Hello BadThad! Thank you for jumping into the discussion!  Quote:
Just a few milligrams. Going to the percent range makes the pH to high and the solution to aggressive (high ionic strength) for light, careful conservation. The goal is having the water do the work, not a buffer. I read this as below 1%, e.g. 0.5% solution? Example, using a scale: weight 0.5g of bicarbonate and add 99.5g of water until we make 100ml? Or is that too much and better closer to 0.1%? Thanks! |
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Bedrock of the Community
United States
19935 Posts |
Quote:
I read this as below 1%, e.g. 0.5% solution? 1 mg = 0.001 g To just barely nudge the pH up from the deionized 6-7 range to a hair over 7 use like 5 mg in 1 to 4 liters of water. Be sure to rinse off with regular deionized water after the soak to be on the safe side. NOT percent, milligrams. It's like a few tiny grains. It's VERY easy to manipulate the pH of pure water. It takes almost nothing to bump it to the acid or base side. Edited by BadThad
04/02/2024 6:20 pm
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Moderator
 United States
95360 Posts |
wow, some real good information here. thanks for this topic.
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Valued Member
Italy
284 Posts |
Quote:
To just barely nudge the pH up from the deionized 6-7 range to a hair over 7 use like 5 mg in 1 to 4 liters of water. Be sure to rinse off with regular deionized water after the soak to be on the safe side Thank you BadThad!  So that would be ... if my calculations are correct .. a +/- 0.0001%-0.0005% solution (1-4 liters with 5mg), right? At these concentrations it's understandable why this might be considered safe. Moreover, considering that distilled water in an open system will become slightly acidic, this is probably a way to prevent that and avoid feeding acing-eating corrosion (maybe "stabilize" is a better term before further treatment?) while water does its job dissolving contaminants. Love how this topic is developing, hopefully we will get much more info/advices/analysis from our great members!  |
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Moderator
United States
95360 Posts |
This is great information here, while I have not used any water on my coins - I'm sure not to use Tap if the thought occurs to me to do so..
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Valued Member
United States
338 Posts |
Why not just stick with 100% acetone and skip the water bath?
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Moderator
United States
187950 Posts |
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Why not just stick with 100% acetone and skip the water bath? Because water is cheaper and if water works, use it. If not, then up the ladder to acetone. Even if water did the trick, I would still do a final rinse acetone to help dry the coin. |
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Bedrock of the Community
United States
19935 Posts |
Quote:
Because water is cheaper and if water works, use it. If not, then up the ladder to acetone.
Even if water did the trick, I would still do a final rinse acetone to help dry the coin. Exactly! Ironically, water is the most damaging substance to coins but it is also the best coin conservation solvent on earth. hehehe  |
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Valued Member
Italy
284 Posts |
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Ironically, water is the most damaging substance to coins but it is also the best coin conservation solvent on earth I read somewhere that water is a more powerful solvent than acetone for inorganic substances. Acetone while being a solvent for both organic and inorganic is less effective for inorganic while being extremely effective for organic. Is this true BadThad? If the above is true it makes sense why acetone alone could be seen as lacking if water is more effective against inorganic grime? |
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Bedrock of the Community
United States
19935 Posts |
Water is the the strongest polar solvent for coins. Acetone has very limited ability to dissolve inorganic substances. Always start with water, the price is right too! |
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Pillar of the Community
United States
7010 Posts |
Commented in order to keep track of this topic for a while and follow "salt" mixture for me experiment with.
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Pillar of the Community
 United States
7936 Posts |
Since the topic has been bumped... Quote:
Acetone has very limited ability to dissolve inorganic substances. Always start with water, the price is right too! And... - Acetone is hazardous. It is highly flammable. If you're using it in your basement and your hot water heater is nearby, the pilot light could start a flash fire. It's like saying don;t play with matches unless you plan to start a fire. |
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Moderator
United States
187950 Posts |
For what it is worth, I use acetone outside on the back patio.
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Replies: 29 / Views: 2,531 |
First Page
Posted 04/02/2024 02:45 am
