Ok so I know a lot of people here use olive oil Is there a better oil to soak them in? Also, will a regular toothbrush hurt a coin? As far as removing the oil, will hand soap work?
Use distilled water to get the first couple layers of dirt. Use olive oil for some really stubborn dirt. Tooth brushes are ok. Also use toothpicks.
The ideal way to remove those green deposits is with a stereomicroscope and a scalpel, but it requires a good amount of skill. The coin is perfectly fine as it is and any other cleaning methods will detract from it.
Use a good grade of high pro raceing oil mixed with a half cup of jet fuel. Light with an extra long stem match and watch the old guy on the coin jump out at you. Rinse with warm clear water save the match and throw the coin away.
yeah, looks good. when you get you coin, make sure none of the green spots flake off any green power with your fingernail....that would be BD...but none of that looks like BD just form the picture. pretty coin, dark and the green look nice i think.