I bought a 2012 Year of the Dragon 999 silver coin. It's a 1/2 ounce. It says "comes in original mint seal". Would that just be a cellophane, or a hard plastic holder? The problem is....I cannot find the actual diameter. Sites say 32.2 mm...that cannot be true. A 1 ounce coin is 32.7mm in diameter. Surely a coin 1/2 ounce less would not be .5 mm smaller.
I bought a 2 ounce version of the same coin, and it came in an airtite directly from the Perth mint. I am guessing your coin might as well. Wait and see what you get. TC
The mint packages them in a hard plastic capsule. FWIW, most of the Perth Mint collectors want the items in the original packaging. btw, your 32.7mm for a 1oz coin is incorrect. The sizes of 1oz silver coins ranges from 37mm up to about 46 and vary depending on mint. If you want to find out the diameters of silver coins go to apmex and check out the specs of the coins, it's a very good education.
I've never purchased a Perth Mint coin that wasn't already in an airtite. As has already been stated, it shouldn't be an issue.
The coin I purchased is not from the perth mint. http://www.amazon.com/2012-Year-Dragon-Silver-Round/dp/B006UXOOK8/ref=sr_1_4?ie=UTF8&qid=1335125358&sr=8-4 It just says "private mint".
I would be wary of "protective plastic" and buy an airtite for it then. If you cannot get a direct fit in that size, then just get the closest one you can with the ring so it does not move around. TC