Cleaning question

IstilllikeZARcoins

I recently soaked 2 coins for a month or so ( perhaps 6 or 7 weeks ) in olive oil.

The coins had verdigree on them so I ran a little experiment.

5 minutes ago I took the coins out of the oil, washed them under water and patted them gently dry in some kitchen towel.

Unfortunately the verdigree remained ( the coins were fairly worthless anyway ) however the luster on the coins seems to be a bit brighter from what I remember.

Is this a usual effect from an oil soakage ? I am not sure if I like the new surfaces ( the colour of them ).

Let me perhaps put it this way: If I were to soak a coin worthwhile of slabbing in oil for a month or two and then were to send it in to PCGS to get slabbed. Would the graders be able to pick up on the fact that the coin had been soaked in olive oil ?

Disclaimer: I would never, ever try to clean a coin of any value and I would certainly not clean any coin and then send it into any grading service.

I have a few worthless silver coins in the oven at the moment - I'll try to photograph them later if the experiment is succesful ( not that it's an experiment - it's just seeing what will happen ).

theboz11

There is a difference between cleaning and restoration of a coin or medal. NCS restores coins and submits them directly to NGC every day, and they get graded. Try disloging the gunk with a natural Thorn, like a rose thorn. It is tedious work to do correctly.

Hussulo

All olive oil has some level of acid in it. The acid level in Extra Virgin olive oil shouldn't be above 1%. Virgin olive oil has an acid level around 3% because its pressed more times and "normal" olive oil is the most acidic.
Any form of acid left on a coin too long will damage it in some way. I know some Roman coin collectors use this technique to clean coins and it seems to work for some, but I don't know if I would use it on milled coins.

IstilllikeZARcoins

Thanks for your replies.

I have used NCS successfully in the past and I take your point aboard regarding the difference between cleaning and restoration.

The thorn technique really isn't worth it as these coins have no value and I have better things to be doing with my time ( new father, work, households chores etc ). Coins are a relaxing hobby though I must admit its just that I am short on time.

Interesting to hear about the different acidity levels of the olive oils - I guess it makes sense.

I've got a few good results from the oven and its training my eye to see more AT colours.

I'll post a few when I have more time ( when the Mrs has gone to bed ).

JZrarities

The olive oil with give it a better look of luster, but unfortunately, it will slowly return to normal as the oil dries out.

A bottle of 'Blue Ribbon' is a better oil product often used for conserving copper (I use it on my Medals)

-Jeff

TwoKopeiki

Jeff, I agree about the "Blue Ribbon" - great copper conserver. Don't forget to get the oily residue off if you decide to submit to a TPG, though.

IstilllikeZARcoins

Interesting - I just split the 'would you like chips with that' coins ( the oven baked ones ) into groups of low toned, medium toned and high toned.

Among the high toned spectacular coins there were a few with blue toning all over. I rubbed one with my finger to get a fingerprint of the coin and rubbed the blue toning away. I did the same to a second coin and that blue toning came away very easily too.

Why does that happen ?

coinkat

One can tell if a coin was in blue ribbon or olive oil...