My NOCv3 (EPCC) is the first deck of my collection which is non-USPCC. But I had a very bad experience on it. After the first 10 minutes playing on it, one of the cards got a big black scratch on the back. I know it is done by my nail. But I had clean my hands and let them dry before unbox and touching the cards. It is a mystery that where the black color comes from...
Regarding the stock, I think the NOCv3 is stiff, and durable. It is made of paper but on the hands it feels a bit like plastic. It is relatively thin when compare with normal bike, but it is as heavy as the old OHIO premium casino Bee. An interesting deck. What I don't like is the finish (coating?) seems a little bit shiny (and oily) and it feels like plastic.
Maybe the black color scratch is only an isolated case because of my bad luck.
The black color isn't from bad luck or anything of the sort. It's from the pasteboard itself.
Playing cards are made by layering two sheets of paper and gluing them together under pressure - the end result is called pasteboard. In a good-quality, "black core" stock, the glue is heavily mixed with graphite, which makes the cards opaque - without it, you'd be able to see through a card when you hold it up to a strong light. Cheap playing cards, including some "blue core" stock, have this translucent quality, as do specially-gaffed Hofzinser magic cards.
When you nicked the card, you cut through the upper layer of paper and into the glue area, revealing the graphite. You might also notice, especially with USPC stocks, that if you have even a small amount of moisture on your hands from water, sweat or even the natural oils in your skin and transfer it to the edge of a card, a black stain appears at the edge - again, this is the graphite, made visible by the moisture. My guess would be that the glue is at least partially water-soluble while the graphite mixed it in is not, so the water melts some of the glue and leaves the graphite exposed. I frequently end up with black stains on the edges of my USPC decks which are used for performance under a variety of not-always-ideal conditions and it used to drive me crazy trying to figure out what caused it - I thought it was dirt transferred to the card, but it wouldn't rub off with an eraser!
Not all cards suffer from this design feature. Even though they're layered pasteboard and made with a black core, Lee Asher's Fournier 605s are not susceptible to water damage in this way - you can in fact briefly submerge an entire card in a glass of water, remove it and wipe it off in order to clean the card, despite that it's made of paper. I suspect that it has something to do with how the cards are made - they might be laminated with their plastic coating AFTER being cut rather than before, or it might be something about the way they're cut that seals the edge to prevent water damage upon submersion, or maybe even that they place the graphite only in the center of the card, leaving it out of the border area, thus there's no graphite remaining to make the black marks or perhaps they use a superior glue that doesn't dissolve in water. Lee would know better than I would!