Five Years of Olive Oil

I thought I would share with you the results of long-term immersion of some
uncleaned bronze ancient coins in olive oil. While I did not design this to
be a scientific study, I found the results to be interesting and hopeful
(mainly because I am lazy and don't want to work too hard on a single coin).
All of the coins started out as little unidentifyable orbs of dirt and
organic muck that did not yield any detail under a soaking in soapy water
and some toothbrush scrubbing.

I placed one group of cheap roman coins in about 2 oz. of olive oil, in a
airtight container, and put them in the garage for five years. There they
(and the olive oil) were subjected to temperatures extremes from 100 degrees
Farenheight in the summer to minus ten or so during the winter.

[ An aside: I also I placed another two groups in my basement in liquid
dish detergent. Not much good came of these latter two groups, other than
some interesting biology.]

When I opened the container from the garage, I was surprised to find a
gritty slurry in it. After I removed the coins and rubbed my thumb over
them under some running water, it became apparent that the patina was gone
and the coins were showing their original brass. An example of what came
out is shown in the top coin he

http://i44.photobucket.com/albums/f1...bv-cleaned.jpg

http://i44.photobucket.com/albums/f1...ev-cleaned.jpg

Mind you, the olive oil did all the work here, aside from the wipe from my
thumb under water. It seems that the grit in the olive oil slurry could
only have been the patina, which broke off in pieces. I believe the
freeze/thaw cycle could well have had an effect here, especially given the
results of my second success. The two coins that had one side against the
bottom of the container (where they were not exposed to much olive oil)
looked almost completely uncleaned on that side.

My second group consisted of five uncleaned greek ancients, which I siaked
in olive oil in the basement for five years (temperature there is almost
constant at about 62 degrees Farenheight). The best of these are shown in
the above links. Again, the olive oil did all the work, other than a swipe
with my thumb. Interestingly there was no slurry, just the usual
copper/cupric oxide bluegreen color in the olive oil. I am much more
pleased with these results, as I prefer a nice patina.

I think five years was a bit long for the good of the coins. I like the
patina on old bronzes; some shorther period of time, perhaps three years,
might be optimal in my conditions and with the same set of coins.

I have placed more coins in my basement and will keep an eye on them for the
next few years. I will report back then.

Best regards to you all.

--Keith Fletcher

p.s. No, I never changed the olive oil. I only used a couple of ounces in
every case.

What made you decide on five years?

The Space Boss wrote:
What made you decide on five years?


The mathematical formula for letting sit in olive oil is inversely
proportional to the era that the coin was originally embedded in the
horse manure (Greek or Roman), multiplied by the frequency of epic wars
fought on the ground above, minus the square root of the differential of
soldiers on the take (give or take a few gamblers), plus the integer of
the compounded interest on a loan from the Pythoness, at a buck two
forty for any given year, save leap years. Then you have to figure in
the vintage of the olives. It gets pretty tricky, so mostly they just
sit on the shelf while being thought about until they ripen up on their
own. What was the question again?

There was not much progress after a year, so I let things soak a while
longer.

--K

"Fletch" wrote in message
...
There was not much progress after a year, so I let things soak a while
longer.

--K


I had a batch or six I played with. I put them in olive oil and rinsed them
every week
in acetone and used a toothbrush on them. Took a lot less than 5 years to
get similar
results. I might have messed with them for three months. When I started
they looked like
flat rocks. Don't have any images and I gave them all away as curiosities.

Dale
need to try that again sometime

Love the last piece on the right, now that is a wonderful coin!

Yes, I wonder what the star below the horse is about. A mintmark perhaps?

--K

"Sibirskmoneta" wrote in message
...
Love the last piece on the right, now that is a wonderful coin!

On Wed, 31 May 2006 03:12:48 GMT, "Fletch"
wrote:

I thought I would share with you the results of long-term immersion of some
uncleaned bronze ancient coins in olive oil. While I did not design this to
be a scientific study, I found the results to be interesting and hopeful
(mainly because I am lazy and don't want to work too hard on a single coin).
All of the coins started out as little unidentifyable orbs of dirt and
organic muck that did not yield any detail under a soaking in soapy water
and some toothbrush scrubbing.

I placed one group of cheap roman coins in about 2 oz. of olive oil, in a
airtight container, and put them in the garage for five years. There they
(and the olive oil) were subjected to temperatures extremes from 100 degrees
Farenheight in the summer to minus ten or so during the winter.

[ An aside: I also I placed another two groups in my basement in liquid
dish detergent. Not much good came of these latter two groups, other than
some interesting biology.]

When I opened the container from the garage, I was surprised to find a
gritty slurry in it. After I removed the coins and rubbed my thumb over
them under some running water, it became apparent that the patina was gone
and the coins were showing their original brass. An example of what came
out is shown in the top coin he

http://i44.photobucket.com/albums/f1...bv-cleaned.jpg

http://i44.photobucket.com/albums/f1...ev-cleaned.jpg

Mind you, the olive oil did all the work here, aside from the wipe from my
thumb under water. It seems that the grit in the olive oil slurry could
only have been the patina, which broke off in pieces. I believe the
freeze/thaw cycle could well have had an effect here, especially given the
results of my second success. The two coins that had one side against the
bottom of the container (where they were not exposed to much olive oil)
looked almost completely uncleaned on that side.

My second group consisted of five uncleaned greek ancients, which I siaked
in olive oil in the basement for five years (temperature there is almost
constant at about 62 degrees Farenheight). The best of these are shown in
the above links. Again, the olive oil did all the work, other than a swipe
with my thumb. Interestingly there was no slurry, just the usual
copper/cupric oxide bluegreen color in the olive oil. I am much more
pleased with these results, as I prefer a nice patina.

I think five years was a bit long for the good of the coins. I like the
patina on old bronzes; some shorther period of time, perhaps three years,
might be optimal in my conditions and with the same set of coins.

I have placed more coins in my basement and will keep an eye on them for the
next few years. I will report back then.

Best regards to you all.

--Keith Fletcher

p.s. No, I never changed the olive oil. I only used a couple of ounces in
every case.


Wow, I thought i was the only one too lazy to finish what I started!
I have a Dewar's crystal rock's glass sitting on a shelf in my office.
It contains maybe 4 ounces of olive oil and 100 to 150 coins, mostly
AE4 to AE3 size, with acouple of follis thrown in. This summer marks
the tenth year that they have been sitting there, uncovered, at a room
temperature ranging from 68 to 83 degrees. Other than the olive oil
taking on a pleasing light greenish tint, there has been very little
change. The oil is still clear, and the coins look no different than
they did in 1996 when I abandoned them there. Every year or so I take
one or two out to clean them, but there seems to be little or no
change in their condition, and the condition of their (light)
encrustations, over time.

Somehow, I was hoping for more from 10 years of treatment!


Reclining Buddha

The Original Couch Potato!

Fletch wrote:
I thought I would share with you the results of long-term immersion of some
uncleaned bronze ancient coins in olive oil. While I did not design this to
...

fletcher the reason you're seeing more damage in the first group is
that the high temperatures turned the oil rancid. rancid oil = higher
acid content. it was telling that you said the "olive oil did the
work". it wasn't. it was the acids that are in the oil that did it. and
just as you wouldn't dunk your u.s. coins in acids (mild or otherwise)
you shouldn't do it to ancient coins either... unless you don't mind
losing the patina.

no museum or coin dealer would ever mess with something as provincial
as olive oil. they'd use a pick, a microscope and a lot of patience to
restore the item. give it a try and you'll prove to yourself not only
much better results but also getting the job done in a half hour rather
than five years.

and if you still insist in the romance of oil soaks you should try an
acid-free type like mineral oil or synthetic engine oil.

ras of dirtyoldcoins.com

dirtyoldcoins guy, i am WAY impressed. (but I still don't trust myself with
a pick.)

what exactly happens when oil turns rancid? i mean, chemically?

--keith