From the Aug. 31, 2015, edition of Coin World:
This month I would like to share with you a few email queries I received. One reader wrote:
“I was wondering if ‘Attaboxes’ are suitable for storing coins, medals and paper money if they are placed in a home safe? The box is described as being made from thermoplastic (injection molded) polycarbonate. I plan on storing my collection in an acid-free box and then putting it in the Attabox. If this is not safe, would you recommend using the metal bond boxes used in bank vaults and home safes instead?”
Good question. Attaboxes (www.attabox.com) are designed to provide a watertight outdoor enclosure for electrical equipment. The boxes are made from polycarbonate and then made watertight with a neoprene gasket. Polycarbonate is considered a “safe” material for intimate contact with collections, but neoprene is not.
I contacted the manufacturer and he said that their gaskets are removable and could be easily replaced with a different material.
So, if the reader removed the gasket and replaced it with a safe foam such as Volara (a closed cell polyethylene foam) the boxes would be fine for storing numismatic collections in a safe.
Alternatively, he could simply remove the gasket and use the box without one.
A bond box would be fine. These boxes are now also made from polypropylene, a safe plastic.
Another reader wrote with the following question:
“I know that PVC is bad for coins but what about Styrofoam? I have purchased some rolls of BU coins and, to keep the coins from rattling around, the seller placed a Styrofoam peanut on top of the coins. I have removed the peanut as I was not sure it was safe. Can you please advise."