Plastic Ain’t Forever..... Is It?

IMHO... I would assume for the TPG'S, If you keep them cool and dry, They should last for eternity. I think PCGS & NGC are in the same boat.

 

Log in or Sign up to hide this ad.

The very north can have 24 hours of sun lol

 

...if the window is a skylight!

 

When I was in Fairbanks, Alaska, we got about 21-22 hours direct sunlight a day.
I was about 100 miles south of the Arctic Circle so no 24 hours direct sunlight.
BUT
When I was at the US South Pole Station it was 24 hours direct sunlight.
I was there only in their summer (1 Nov to mid-Feb).
Sun was up when I got there and stayed up the whole time.
But we were about 20 feet down so you had to go outside to see the sun.

 

There's a bunch of grade misses on eBay that are slabbed that will run about 5-6 bucks each if you wanted a cheap coin to crack out for the experiment

 

"Just one word...Plastics..."

 

Then a "clear-coat" is offered to toughen and re-seal the plastic.

 

Interestingly window glass filters out most (if not all) UV.

 

Or, someone who cracks them out as a matter of course could just send him one...

 

It's basically the same cost for a bubble mailer with slab fragments

 

Will the ones with the anti-reflective coating have an effect though? I'm unsure if it's coated on both sides, but maybe if it's on the underside, then maybe the plastic is affected.

 

To get into "you're both partly right" territory:

UV comes in different "colors" just like visible light. After you go past blue and violet, you get to UV-A, just a bit more energetic than visible light. Keep going, and you get to UV-B, more energetic and damaging, then UV-C, very dangerous indeed. Beyond that is EUV ("extreme UV"), then X-rays.

UV-C and everything above it gets absorbed strongly by air, so we don't get much of it from the Sun at ground level.

UV-B gets through the air, but window blocks it. You need something like a quartz window to let it through. Borosilicate glass (old-school Pyrex, before that brand got sold out) lets through some.

UV-A gets through normal glass to varying degrees.

Even blue or violet visible light can cause yellowing damage, so a paper left on the indoor side of a windowsill will turn yellow with time, even if UV doesn't get through.

 

Who needs plastic anyway.

 

Thanks, I was thinking mainly of UV-B. Why I had to use quartz cuvettes when running vis/uv spectra.

 

Yup. Quartz passes all the way up into UV-C, and way into the IR (but not quite into the thermal IR ranges). Just a shame it's so hard to work.

 

But you don't need special coating to block UV-B

 

Forgot that part. Most kits do also include the clear coat finish, however some do not.