I found this Seated Liberty dime metal detecting. It has grayish purple tarnish from sitting in sandy soil for over 100 years. I haven't done anything to it besides rinsing with water and removing large chunks of dirt with a wooden toothpick. There is encrusted dirt/sand that I haven't tried to remove. I can't tell whether it is an 1873 or 1878, or if there is a CC mintmark. Maybe someone with more discriminating eyes could tell whether it is a "3" or an "8." I think I can see a CC mintmark, but it might just be my eyes playing tricks on me. I am looking for advice on how to clean this coin if at all. I don't want to ruin the coin (more than it is already damaged) in case it has a CC mintmark and is actually worth something (1873 more so than 1878). But like dug ancient coins it may be appropriate to do some kind of cleaning. I have read about all kinds of cleaning methods including ammonia, peroxide, vinegar, lemon juice, baking soda and aluminum foil, etc. Thanks for any guidance
If this was an ancient coin, I would soak in water, rub with fingers. Analyze remaining deposits. Then, for major hard limestone or other rock encrustation, sodium hydroxide. For any sort of iron oxides or horn silver, sodium thiosulfate. i would avoid acids as a general rule.
Thanks, I will look into those methods. I am not sure of it but I think the tarnish is silver sulfide.
Aaand this is why another set of eyes helps. I think you're probably right. And yet there I was sitting cross-eyed trying to see a "3" or an "8".
I usually didn't dig up Silver like this in this condition and I've dug up several from this time period. I'm just wondering if an initial rinse in distilled water than Acetone would work??? Anyone know? Calling @paddyman98 ?
Using any method to clean a coin will only let those of interest know it has been cleaned. In turn it will lessen the value. If you plan to keep it then the decision is yours, good luck.
Seeing that the coin is damaged (very pitted surface) and won't be worth much no matter what, I decided to remove the encrusted dirt and remove enough tarnish so that the details are easily legible without the need for a sidelight. I soaked the coin in ammonia for one minute on each side and that took care of the encrusted dirt. I used the spit and aluminum foil method to remove tarnish (it was silver sulfide as I suspected). I didn't go overboard trying to make the coin shiny. I am pretty happy with the result. As you can see the surface of the coin is very rough, but that is what 100 years in bad ground does to silver. And @Omegaraptor, you were spot on!
I agree, damaged. It is what it is. I would just leave it be. The luster is long gone from this coin. I've dug many Barber dimes just like this and it was in fertilized sandy soil. On a side note, Nice find! I would head back there to find its Sister coin.
Neat find. The area you found it was probably sprayed with harsh chemicals such as fertilizer. Glad you were able to at least figure out the date.
Good work cleaning that up. It looks much better now. Plus, now you have the experience for the future. I detect too, but have yet to find an 1800s silver.