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  Cleaning and caring for Robbins medals

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Author Topic:   Cleaning and caring for Robbins medals
mensax
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posted 04-07-2004 06:58 PM     Click Here to See the Profile for mensax   Click Here to Email mensax     Edit/Delete Message   Reply w/Quote
Does anyone have any advice on the care and cleaning of older Robbins medallions?

mconway
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posted 04-08-2004 09:06 AM     Click Here to See the Profile for mconway   Click Here to Email mconway     Edit/Delete Message   Reply w/Quote
Does cleaning impact valuation of Apollo mission Robbins medallions?

mensax
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posted 04-10-2004 08:43 AM     Click Here to See the Profile for mensax   Click Here to Email mensax     Edit/Delete Message   Reply w/Quote
That's a good question. I wish I had an answer!

My brother collected coins for many years and I can still remember him telling me that "a cleaned coin was a ruined coin" and "that a coin is what it is." Whether or not cleaning affects medallions or not is a different situation, I would think.

I have seen many grungy medallions for sale at auctions, and I always have wondered why someone didn't take the time to improve their looks. Or, if I bought one how I would go about it. I do know that IF you were to clean one, you'd need to do it right. Remove the stains and tarnish without affecting the patina.

You wouldn't want to use an abrasive cleaner that could scratch, you wouldn't want to dip it in an all purpose cleaner. You'd want to make sure and not eliminate the depth that the older Robbins have... the raised surfaces are much brighter than the recessed areas.

Richard
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posted 04-10-2004 09:32 AM     Click Here to See the Profile for Richard   Click Here to Email Richard     Edit/Delete Message   Reply w/Quote
That is a good question. Yes, when dealing with any article, especially antiques and coins, cleaning will take away from the value. However, I do not believe that this holds true with Robbin's medallions.

With an antique table, cleaning will take away the patina. This sign of age and the color it provides are what makes it more desirable. With coins, the greater value is with the least amount of handling and circulation. Cleaning can detract from this and unless the coin is "uncirculated" and pristine, it can make it look artificial.

However, with Robbins medalions, the value is secondary to their historical significance. If they were flown vs. unflown, who owned the medallion previously, etc. The condition of the medal is secondary and I feel that a cleaner medal in this case would only add to the value. In fact, Owen Garriott has had all of his medallions encased in a lucite block for display. With a coin collection, this would hurt the value, but with the Robbin's it doesn't. The historical significance is still there.

rocket ron
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posted 04-10-2004 11:07 PM     Click Here to See the Profile for rocket ron   Click Here to Email rocket ron     Edit/Delete Message   Reply w/Quote
I'll be interested in the response from Robbins. I had thought about having my Apollo 11 medal cleaned, but have the same questions on the condition and value of a cleaned medal.

James Brown
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From: Atlanta, Georgia, USA
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posted 04-11-2004 08:19 AM     Click Here to See the Profile for James Brown   Click Here to Email James Brown     Edit/Delete Message   Reply w/Quote
Here is the response I received this morning from Robbins:
From what I understand most aficionados (sp?) do NOT want a cleaned, shiny medallion/coin. To quote one "we want the grunge". So while it is your choice, I think it is best to leave well enough alone (even cleaning by Robbins takes away some tiny amounts of metal and risks overpolishing of the supposed-to-be-shiny areas).
Hope this helps.

spkjb
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posted 10-02-2011 11:05 AM     Click Here to See the Profile for spkjb   Click Here to Email spkjb     Edit/Delete Message   Reply w/Quote
Does anyone have data or an opinion about oxidizing of the medallions? Is this a concern? Are there other types of degradation to expect?

Editor's note: Threads merged.

rgarner
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posted 06-23-2013 05:27 PM     Click Here to See the Profile for rgarner   Click Here to Email rgarner     Edit/Delete Message   Reply w/Quote
I was wondering if anyone had any advice on cleaning a Robbins Medallion?

I have an unflown Apollo 15 Robbins which needs a bit of TLC. Anyone have any experience?

I have heard hot water, baking soda and salt on tin foil. But I don't want to risk such a valuable piece of my collection!

Editor's note: Threads merged.

YankeeClipper
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posted 06-24-2013 12:45 AM     Click Here to See the Profile for YankeeClipper   Click Here to Email YankeeClipper     Edit/Delete Message   Reply w/Quote
First it is important to understand a little of the chemistry of the metal.

Most Robbins medallions, including your unflown Apollo 15, are Sterling Silver - an alloy of Silver that consists of 92.5% pure Silver (Ag) and 7.5% of other metal, usually Copper (Cu). Fine Silver (99.9% pure) typically is too soft for practical objects. Alloying with Copper maintains the silver color of the metal, while increasing its strength. However, the Copper is much more susceptible to oxidation and corrosion, so Sterling Silver tarnishes more easily than Fine Silver.

10K and 14K Gold Robbins medallions are Gold (Au) alloys and while reasonably resistant to tarnish/corrosion will still undergo chemical reactions depending on the alloy metals present.

Dihydrogen Monoxide (H2O), Sodium Chloride (NaCl), Oxygen (O), Sulfur (S) and Sulfides will all act over time to tarnish Sterling Silver. Typical tarnish often seen is Disilver Sulfide (Ag2S) (Black), Silver Chloride (AgCl) (White), Disilver Oxide (Ag2O) (Black-Dark Brown), Copper Carbonate (CuCO3) (Blue-Green Verdigris), Copper Dichloride (CuCl2) (Light Brown turning to Blue-Green), Dicopper Oxide (Cu2O) (Red) and Copper Oxide (CuO) (Black). Handling, humid or damp storage atmospheres, and surface damage via scratches, abrasions, corrosion will all influence the exact chemical reactions which occur. A short review on silver tarnishing from the V&A museum can be found here. Unfortunately, the humid climate at both Cape Canaveral and Houston is not a great storage environment for Sterling Silver medallions.

An excellent first choice product for gently removing and preventing tarnish on Robbins medallions is Goddard's Silver Polishing Cloth which is impregnated with special proprietary agents. You should be able to buy it in any large Tescos or Sainsburys in the UK.

Slow and gentle use of a Goddard's Cloth, taking care to try and preserve the shading effect on the medallions is key. The scale, location and permanence of any tarnish/corrosion and the value of the medallion will determine how much cleaning you attempt - if in doubt, less is better! If you think a little extra help is required then a small dab of vinegar (which is 5% Acetic Acid CH3COOH) may assist in solvating a spot. Avoid using bleach, baking soda, or any other strong or abrasive chemicals. There is always the option of sending the medallion back to Robbins for professional cleaning.

Storage options for Robbins medallions include their original hard plastic boxes, microfibre cloths (the ones that come with sunglasses), encasing in lucite, and NGC encasing ("slabbing"). Small packets of Silica Gel - Silicon Dioxide (SiO2) are an effective storage dessicant and will remove atmospheric moisture to prevent the tarnish process.

Don't store Silver medallions in very light plastic flip cases for long periods as a chemical reaction can generate acid that will attack the silver surface. Don't glue medallions directly to mounting mats or store medallions in direct contact with tissue/paper/cardboard as the acids in the paper products will attack the silver surface.

Handling is best done wearing white cotton gloves (such as the ones worn by museum staff or jewellers) to avoid getting moisture and oils on a medallion. At the very least ensure that hands are clean and dry and the medallion is held by the edges.

rgarner
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posted 06-24-2013 05:20 AM     Click Here to See the Profile for rgarner   Click Here to Email rgarner     Edit/Delete Message   Reply w/Quote
YankeeClipper, you're a scholar and a gentleman! (unless you're a woman, then you're a gentlelady). Thank you very much for that in depth answer. It really helped.

YankeeClipper
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posted 06-24-2013 11:35 AM     Click Here to See the Profile for YankeeClipper   Click Here to Email YankeeClipper     Edit/Delete Message   Reply w/Quote
No problem.

If you don't like the idea/cost of NGC encasing, then a top tip is the ultrafine microfiber cloths/bags produced by Microclair and available at any branch of Sunglass Hut.

Microfiber cloth protects from moisture/oils/scratches, folds neatly around a Robbins medallion and can be popped into a microfiber sunglasses bag for added protection. Black microfiber cloth is great for display as it accentuates the silver (jeweller's trick) and is perfect if you want to pass the medallion through the hands of friends as it will protect from the inevitable moisture and salts from perspiration and skin oils. The little plastic flip cases that the cloths come in can also be used for temporary transportation of a medallion.

Goddard's Cloths are great for cleaning but do not store your medallion in them as they could remove the medallion shading effects over time.

Finally, if you are thinking of encasing the medallion in a Lucite acrylic resin or equivalent, then do not display the piece in direct sunlight or a brightly lit room. Over time UV light will photochemically degrade the transparent resin resulting in a yellow appearance.

SkyMan1958
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posted 06-24-2013 12:47 PM     Click Here to See the Profile for SkyMan1958   Click Here to Email SkyMan1958     Edit/Delete Message   Reply w/Quote
As a coin collector for ~ 25 years I would recommend against cleaning a Robbins medallion unless you know what you are doing.

There is an organization called Numismatic Guaranty Corp. (NGC) that has been encasing Robbins medallions in plastic holders for some time now. Note the medallion is NOT embedded in lucite, you can pop the medallion out of the holder any time you wish by cracking the holder open. NGC will "grade" the medallion for you (most likely it would grade somewhere in the range 60 - 70), with the higher the grade the better the condition of the medallion.

This placing a coin or medallion inside a holder is called slabbing. The slab, will protect the medallion if it is dropped etc. The downside is that you are no longer able to hold the medallion itself in your hand, but hold the slab (the plastic encased medallion) instead. If you look at any recent Heritage space memorabilia auction catalogue (or on their website archives) you'll be able to find plenty of slabbed Robbins.

NGC has a daughter service called Numismatic Conservation Service, NCS, which will clean a coin or medallion before NGC then slabs the coin or medallion. If you are concerned about your Robbins' condition I would recommend that you let the professionals take care of it. Send your Robbins to NCS and then have NGC slab the medallion. Here is the link for NGC. You will find the link for NCS at the bottom left corner of the NGC webpage.

While this is not a Robbins medallion, here is a $2.50 coin that McDivitt took with him on Gemini 4 that has subsequently been slabbed by NGC...

YankeeClipper
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posted 06-24-2013 06:01 PM     Click Here to See the Profile for YankeeClipper   Click Here to Email YankeeClipper     Edit/Delete Message   Reply w/Quote
The advice on NCS/NGC is sound advice and a great storage/display solution.

Each Robbins medallion has to be considered individually starting with the original owner-curator. Some astronauts e.g. Dave Scott, Charlie Duke, Jim Lovell appear to have stored their medallions very carefully over the years. A lot of their medallions would grade MS66 - MS69 and require minimal action to maintain their condition.

Other medallions have passed through multiple owners and storage conditions over the years and have suffered from the handling and lack of TLC. They retain value by virtue of provenance, mission, flown status, scarcity etc. Gentle, careful, sparing, and peripheral cleaning with a Goddard's Cloth as used by professional museum conservators is not going to drastically alter the existing/future condition or value. If done carefully it may improve the appearance and retard any further deterioration.

The less cleaning the better with no cleaning being the optimal scenario. Cleaning will remove microscopic metal surface layer(s) and the fresh surface will require protection. The reality is that Sterling Silver will always be susceptible to chemical reaction over time. The best you can do is to control the immediate environment and slow that process by restricting handling and humidity (e.g. with NGC encasing) and achieving a steady, protected surface state.

Ultimately, curation of Robbins medallions requires careful thought and the condition and value will determine much of the conservation effort that is made.

Greggy_D
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posted 06-24-2013 06:11 PM     Click Here to See the Profile for Greggy_D   Click Here to Email Greggy_D     Edit/Delete Message   Reply w/Quote
Just curious, how is provenance proved when having a medallion encased by NGC? What type of evidence do they need to declare a medallion is from a certain astronaut's collection?

SkyMan1958
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posted 06-24-2013 06:57 PM     Click Here to See the Profile for SkyMan1958   Click Here to Email SkyMan1958     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by Greggy_D:
What type of evidence do they need to declare a medallion is from a certain astronaut's collection?
In the case of the GT-4 quarter eagle the coin had already been slabbed by the time I got it. Accompanying the coin was a Novaspace CoA signed by McDivitt, as well as the original bill of sale.

My best guess is that the previous owner showed NGC the CoA to verify the bonafides of this coin. One would assume that a CoA from the astronaut would do the trick for a Robbins.

rgarner
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posted 06-25-2013 04:13 AM     Click Here to See the Profile for rgarner   Click Here to Email rgarner     Edit/Delete Message   Reply w/Quote
Well, what I intend to do is frame the Robbins along with an Apollo 15 cover signed by all three astronauts along with a very high quality photograph. We are talking acid-free matting, UV protection glass, museum quality basically.

I will also be adding a long strip of flown Apollo 15 material to the display as well.

I am not comfortable cleaning the Robbins myself I'll be honest — I have been looking for a UK company who know what they are doing. Robbins are not like any other medal. I'm thinking of just leaving it how it is and displaying it without any such work being done to it.

YankeeClipper
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posted 06-25-2013 02:33 PM     Click Here to See the Profile for YankeeClipper   Click Here to Email YankeeClipper     Edit/Delete Message   Reply w/Quote
Further to the advice given above, the Canadian Conservation Institute has excellent comprehensive advice on the care of medals and medallic art, and advice on Silver care and tarnish removal.

This information is provided solely to give a better understanding of the different problems/solutions/pitfalls pertaining to Silver care. Some of the techniques are strictly for conservation professionals only. Other advice is more generic and useful for everyone: e.g. do not use Latex Rubber gloves to handle Silver as the Sulfur in the rubber will cause tarnish, do not use wooden display cabinets as the acids from the wood will attack Silver, and do not use Polyvinylchloride (PVC) light plastic flips as the plasticizer in PVC is particularly corrosive to medals involving copper alloys. Both articles are worth reading.

In addition to controlling the relative humidity in the medallion's immediate environment e.g. with Silica Gel, control of Sulfur-containing gases often found in urban air e.g. Dihydrogen Sulfide (H2S) is important too.

Pacific Silvercloth, a brown tarnish-preventing fabric embedded with silver particles, can be used to preferentially absorb Sulfur-containing gases. The medallion should be protected with microfiber cloth and then wrapped in the Pacific Silvercloth. Another possible option is to use 3M Anti-Tarnish Strips, special absorbent paper strips that trap sulfides in the surrounding air.

Finally, it is important when examining and admiring Robbins medallions to try to avoid breathing directly onto the metal surface. Exhaled air contains Dioxygen (O2), Dihydrogen Monoxide (H2O) vapour, Carbon Dioxide (CO2), Dihydrogen Sulfide (H2S), and Methanethiol (CH3SH) gasses which are all bad for Silver medallions. And don't get me started if you are fond of a cigarette!

You can probably appreciate by now why NGC encasing is, for many, a preferred option for medallion protection and display.

spkjb
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From: Merritt Island, Florida USA
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posted 08-11-2013 12:01 PM     Click Here to See the Profile for spkjb   Click Here to Email spkjb     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by mensax:
Does anyone have any advice on the care and cleaning of older Robbins medallions?
I have two Fliteline medallions (GT-5 Sterling silver and GT-10 Gold on Brass or base metal) that are slightly tarnished. Today I went to a coin show seeking advice on cleaning and storage.

Cleaning: There seemed to be no consensus. The basic answers I received were:

  1. Do Nothing (two recommendations)
  2. Use Acetone (two recommendations)
  3. Use "Jewell Luster" (two recommendations)
  4. "Easy Dip" (one VERY adamant recommendation)
  5. Silver Polish (one recommendation)
  6. Soak in "Dawn Dish soap awhile (one recommendation)
All the opinions came with various instructions on how to use these materials.

Can the forum give me feedback on your thoughts regarding the cleaning?

Storage: Basically the folks recommended "slabbing" or storage in acid-free vinyl sheets. I would prefer the micro-fiber pouches that are supplied by "Sun Glass Hut", but they are out of stock. Does anyone know of another source to procure the pouches?

SkyMan1958
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posted 08-11-2013 08:14 PM     Click Here to See the Profile for SkyMan1958   Click Here to Email SkyMan1958     Edit/Delete Message   Reply w/Quote
With regards to Flitelines, you are on your own, e.g. NGC at this point in time does not slab them.

Here is a good write-up on what we know about Flitelines.

With regards to what the assorted dealers told you, Jewell Luster and Easy Dip are the same thing. They are acidic solutions. Silver polish is an abrasive (albeit a mild one). You could try acetone. Here is a write-up on it.

All times are CT (US)

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