Coin Storage

[JeffH]

And the helium in the balloon would have a tiny amount of hydrogen, the smallest molecule of all, which is only present in the atmosphere as a 'trace'.

[Fulvio]

And the helium in the balloon would have a tiny amount of hydrogen, the smallest molecule of all, which is only present in the atmosphere as a 'trace'.

True.

[autocoupler]

Thanks for that. Sounds like no matter what we're using as storage, the better the general environment, the more long term the protection. Also thinking dry climate verses humid climate may be other factors, and I've often wondered about the flukyness of how and where some coins have been stored over the years, especially when say a 1911 penny that is housed in a stapled 2X2 has actually retained a full red condition.

[Fulvio]

the better the general environment, the more long term the protection.

Quite. Environment is massively important. If there are no nasties present, even an unprotected coin can survive well. Whereas its really hard to keep corrosive fumes out of anything.

So a dry, smoke-free, PVC-free environment is a basic starting point. And maybe these glass puppies are the ultimate? :angel:

[Unicorn]

Exterrrrrrrminate ..... exterrrrrrrrrminate ...... :mocking:

[autocoupler]

Interesting. So if a Warren Buffet type was into coin collecting and had their iconic world rarities housed in something like this, with the rottweiler compound controlled by a vacuum switch, all should be good.  

[Unicorn]

These guys can probably help you McDuck ....

[trout]

I recently bought a vacuume sealer that I  use to pack  meat and cheese to take away with us when we do our "Grey haired Nomad" thing because it takes up less space and I can just store the meat in a fridge for a week or so without it spoiling and it saves some space in the freezer for extra icy poles .

I have also used it to store some Coin rolls and baggies only time will tell if this is effective, But it does stop the coins in the baggies from rubbing and bagging because when sealed this way they are held firmly in place and cannot move when handled :good:
Anything that will help prevent contamination from moisture, air or impact is a good thing, Finding the most cost effective, easiest and aesthetic way of doing this is where it gets interesting

[notcb]

Trout,

So long as the material used for the vacuum sealing is an appropriate material for long term storage of metals (such as copper, nickel and silver).

A quote from Wikipaedia:

"The amount of shelf life enhanced by a vacuum bag is dependent on the structure in the material. A standard vacuum bag is composed of a PA/PE structure where PA is for puncture resistance and PE is for sealing. The high barrier category includes the usage of more layers focused on the prevention of oxygen permeability, and therefore shelf life protection. There are two materials used in high barrier structures, polyvinylidene chloride (PVDC) and ethylene vinyl alcohol (EVOH). Shelf life indication can be effectively measured by how many cubic centimeters of oxygen can permeate through 1 square meter of material over a 24-hour period. A standard PA/PE bag allows on average 100 cubic centimeters, PVDC allows on average over 10, and EVOH on average 1 cubic centimeter. Multi-layer structures allow the ability to use strong oxygen-barrier materials for enhanced shelf life protection. The PremiumPack structure is a good example of EVOH based high barrier shrink material."

Notice that the material suggested is of the PVC VARIETY - internal moisture can still leach out the chemicals from the plastic over the long term.


On the other hand the mylar types of bags used for potato chips and kids party balloons are excellent for vacuum sealing as they do not leach out chemicals nearly as much.

Definitely worth checking what material you are using for sealing.

Cheers

Peter  (notcb)

[matgg]

Does anyone know about the VST coin album pages? That is what my grandfather was using when he passed on his collection, and I expanded it in the same way. I couldn't find anything online, but I have a suspicion they have PVC from the smell... am I correct?

[JeffH]

I think your suspicion can be considered a fact.

[trout]

OOP's

[notcb]

Trout,

There is a test you can make to determine whether the vacuum seal film that you use is PVC or not - that is, contains chlorine.

It is called the Beilstein Test which tests for halides.  (including chlorine).

I have used the test on quite a few plastic ring folders which claimed to be PVC free.

*************

There is also a rough burn test which can differentiate between  PVC and Polyethylene materials - they burn differently.

Cheers

Peter  (notcb)

[trout]

I have removed everything from the bags, Not worth the risk :ok:

[Fulvio]

I have removed everything from the bags, Not worth the risk

Probably a good call. Remember that food has different challenges than coins, and materials which work well for one may not be a good idea for the other. PVC being a case in point.

Of course, you can use any material in a sealer, but the bags intended for vacuum sealers have a ribbed structure to facilitate the flow of air out of the bag before sealing. You could try flat materials and see just how much air is removed.. Why not seal a sponge in a chip packet, and see just how flat it gets, and how long it stays that way? As I've said before, chip packets are opaque, but who cares for long term archival storage of bulk coins, right?

BTW, here's the Beilstein test: https://allaboutimages.wordpress.com/2014/06/09/how-to-identify-pvc/



Do NOT try this with rubber materials. Neoprene will give off toxic fumes.