MS70 causes blue toning on copper?

[Hard Times]

There is no MSDS with the bottle when you buy it. So unless it is posted somewhere, it don't say. I am going to do a chemical analysis and try to make some guesses to what is in there based on the elemental compositions - is there Na, etc? I will also do a pH measurement to see if it is an oxidant contrary to the manufacturers claims. Just need time which is very short right now.

[SouthFlorida guy]

 

 

Anyone have a picture of an ms70'd copper coin that has turned bluish?

[Oldtrader3]

You can buy Pecan oil at Trader Joe's.

 

I can not find any MSDS for MS70. It says that is a Detergent, with no acid. There are no ingrediants listed, I do not believe. My guess would be 2% Thiourea.

[michael]

tea tree oil at most local HEALTH FOOD STORE's

 

call first before you make the trip

[Hard Times]

OT3, Isn't thiourea toxic enough that they would have to by law divulge this if it was in there? How can one test for thiourea? We used it in the lab as an indicator to detect Os during distillation, I have used it in TarnX. I suppose I should drop some Os in MS70 and see if it turns pink - that was how we found Os in our distillates using thiourea - pink color when the two mix.

 

If there is thiourea in the MS70, then likely game set match. Here is a paper I just downloaded:

 

Tarnishing Reaction of Copper with Solutions of Thiourea and

Derivatives. Study by Radiotracers

J. Llopis, J. M. Gamboa, L. Arizmendi, and F. Alonso

JOURNAL OF THE ELECTROCHEMICAL SOCIETY May 1962

Vol. 109, No. 5

 

The only remaining issue becomes what are the kinetics? We need it to happen pdq to explain the blue toning. Are the kinetics that fast in a dilute solution?

 

Has anyone tried TarnX for comparison?

[Oldtrader3]

Hard Times, I read the abstact that you cited but not the article because I would have to pay $26. for it.

 

My chemistry is limited to engineering school chemistry 50 years ago. However, observation of MS70 and its reaction with copper coins seems to take place several 100 milleseconds to full change of toning. I would say that coins (circulated Bronze cents) that I dipped just to try the fomulation out, turned at differing rates probably due to surface contaminents on the cents but in any case, the reaction did not take more than a second or so, usually faster. I wish that I could find a MSDS for MS70. Jewel Luster and some of the others are about 2% acid and 5% thiourea. Sorry that I can not be of more assistance.

[Conder101]

If you contact the company they could probably provide an MSDS.

[Oldtrader3]

They have to, if asked, it is the law.

[e1cnr]

I applaud you in your efforts - I have had mixed results with Jefferson nickels and am leary of using it on my 'toners' as sometimes the color disappears.

 

As far as your copper experiment, I wonder if there is much difference in type of coin surface - proof luster, satin luster, old eroded dies, brilliant luster

 

As an analogy, if you blew up the coin surface a million times, would it be a sheet of ice, a sand dune, rolling hills, ....

 

 

because any resulting color is due to ?thin film refraction?

[Conder101]

As an analogy, if you blew up the coin surface a million times, would it be a sheet of ice, a sand dune, rolling hills,

A million times? Think mountain range.

[MikeInFL]

Any updates here? Just curious....Mike

[Hard Times]

Mike, I did the experiments this past weekend and photographed the results. I could give my interpretation of the results, I think it is extremely clear what is going on with the high res pics of before and after, as well as those where I did half a coin. But, until I have quantitative data to back up whatever the final interpretation is, I will hold off. I want this to be a solid piece of research so I need the SEM results and the chemical analyses of the MS70. I can't say for sure how long it will take to get the data - it takes coin to use an SEM (probably <$100 for the amount of time I need), coin to measure the MS70 composition (need to look into this), and right now, I am uber busy at work. So thanks for the query and I will do my best to get this completed asap.

 

Best, HT

[MikeInFL]

No worries. Was just wondering & am looking forward to your observations and conclusions. Take care...MIke

[robec1347]

So I should hold off applying MS70 to my proof copper just a bit longer?

[Hard Times]

Bob, I think you probably know the answer to that based on previous experiments laid out in these boards.........

[Keigwin]

So I should hold off applying MS70 to my proof copper just a bit longer?

I love wry humor.

 

Why delay, Bob? There's no time like the present. I look forward to wonderful images!

Lance.

[Coindude]

So I should hold off applying MS70 to my proof copper just a bit longer?

I love wry humor.

 

Why delay, Bob? There's no time like the present. I look forward to wonderful images!

Lance.

.... Taunter!!

[chinook]

I can see im gonna have to visit this board more than once a quarter.