Possible dangers associated with velour trays?

[Philoromaos]

Are there any known or possible dangers associated with velour and velour affect coin trays other than wear on the high points, due to sliding about? I ask as I've recently noticed 5 or 6 of my denarii have developed a kind of purple staining on the high points of the portraits where they have been in contact with the tray. Lemon juice soaks wouldn't remove the staining but managed to mostly remove them with washing up liquid. I've had my coins in the trays for over a year now and it's only in the last month I've noticed this. Any ideas what may be causing this?


Adrian

[Potator II]

What are your trays made of ?
Plain, real genuine velvet, or some chemical ersatz of velvet ?

[Philoromaos]

They seem to be plastic trays with a soft coating of something unknown to me. They are the standard red trays that came with my Lindner case.

[Enodia]

perhaps it's a synthetic flock sprayed on over the plastic?

this is one reason why i don't like the trays with circular compartments, or others that don't allow room for the flip. they can slide about, the details aren't with the coin, and who knows what this 'stuff' is?
i use the plastic bags to hold the coin (which then goes into the flip). maybe something like that would work to isolate the coin from the tray?

~ Peter

[Potator II]

Ok, then for your valuable items go for wooden framed/velvet trays. They are much more attractive with their deep dark red color and will be softer to your treasures ; for the cost of a very common worn denarius per tray, It's worth the spent IMO

Potator

[dltcoins]

i use the plastic bags to hold the coin (which then goes into the flip). maybe something like that would work to isolate the coin from the tray?

I can't speak for the trays but "plastic bags" sound bad. As soft plastics age, the plasticizing (softening) agent (aka PVC) outgasses a corrosive acid which will attack silver and bronze. Just this afternoon, I broke down a collection of modern coins which had been held in plastic sheets in a 3-ring binder for perhaps 30 years. Some suffered from moderate PVC damage, ranging from light green encrustation on silver coins to an oily green slime over porous surfaces on copper. Only "safe" plastics should ever come in contact with coins!   

[Enodia]

these are archival bags designed for coins, and are readily available in different sizes from many dealers.
i have stored my entire collection (silver and bronze) this way for over twenty years and i've had no adverse effects whatsoever... no corrosion, BD, or any discoloration at all. what they do though is provide a buffer from the friction the coin can suffer from even the best flips.

~ Peter

[Optimo Principi]

I keep my entire collection of silver denari on conventional velvet lined trays, I can't say I have noticed any wear to my coins. Are people really suggesting this is now an unsafe way to store them? Why are these the standard trays that are sold at every coin show and website if they are not good for the coins?

[areich]

The material is abrasive so coins get worn, especially if they've been taken to coin shows for years and years
without being sold.

[Optimo Principi]

I want to stick with trays - anyone know what the highest quality coin tray are that minimise abrasion?

[silvernut]

The material is abrasive so coins get worn, especially if they've been taken to coin shows for years and years
without being sold.

Is real velvet (not its synthetic version) really abrasive to the coins? I was planning to get a wooden cabinet lined with velvet for longer term storage of my denarii. Not that the coins will move around, but nevertheless, I'd like to know.

Regards,
Ignasi

[Will Hooton]

I use trays too. Mine are made by Abafil of Italy but rather than being velvet, they are felt. Velvet ones are more expensive but I expect felt is a lot more abrasive. However, I use paper backing and since I don't live on a boat, I dont really expect the reverses of my coins to be worn smooth.

http://www.abafil.com/eng/prodotti/prodotti.php