Hi - This is my first time posting on the forum but definitely not my first time visiting it; this site has been a valuable resource for information so I would like to seek your advice about a recent vintage pen purchase.

I bought a restored Pelikan 140 with a needlepoint flex nib and when it arrived, I noticed that a portion of the barrel looked like it was cracking from the inside. It's not a crack down the barrel, but looks like crackle glass or shattered windshield, but on the inside and visible between the green stripes. I tried flushing with water to see if it would clear it out, but it had no effect.

I asked the seller about it and was told that this is a cross hatch pattern done purposely to make the plastic stronger and resilient to impact. The pattern does not look regular to me (yes to irregular shattered/crackling glass look, not cross hatch) and is confined to a small section of the barrel (it's just in one spot above the the pen grip and does not go all the around the barrel). It really does look like vintage crackle glass (I happened to have inherited my grandma's collection of crackle glass so I am familiar with the look), but I have never seen it in a pen. Does anyone know what this is, what would cause this?

The good news is that the seller has agreed to the pen's return and apparently has another buyer lined up for it. I would still like to know what this is, however, for my own edification because I love vintage pens, and if there is anything that I can do to prevent it from happening to my current and future vintage pens... Thanks!