Coin cleaning

Hi, I am new to the forum. I found these two coins metal detecting today in southern England (I have put a one pence coin next to them for scale). It is very difficult currently to see any identifying details, but - after reading up online - I am worried about damaging them by trying to clean them. I would appreciate any advice on how to clean them, so that it might be possible to work out what they are.  Many thanks

I'm pretty sure they are beyond being dirty needing cleaning. More like the entire surface is corroded beyond any chance of identification. I don't think you can do anything to damage them more than they are.

I did think that might be the case. Shame. 

They may indeed be too corroded for identifying,  but try soaking them in purified water for a week  then brushing with a soft toothbrush.  Then repeat the process.  I've had coins soaking for a year or two. It's amazing what you can eventually  make out.  

James

I have a lot of this tabe of coin(pennies) but i haven't ieda how to cleaning them 

I am going to give that a try and see how it goes. Many thanks

You may try soaking them in demineralized water and freezing. Expanding ice will release all dirt and some rust. 

I've had some success in cleaning heavily corroded copper. First, apply a few drops of vinegar, and let set for a few minutes. Then lightly go over it with a graphite pencil. Graphite is a lubricant, and by itself won't further damage the coin. But the copper oxide is harder than copper, so it's good to flush with water and repeat. With patience you can achieve good results. Stop when bare metal starts to appear.

Be aware that vinegar is corrosive and at the end needs to be thoroughly rinsed and neutralized with baking powder.

Thank you for the suggestions. I will give them a try. Many thanks