Black-core stock

Black-core stock: Card paper with an opaque black middle layer that prevents light from showing card faces through the back.

Black-core stock is the industry standard for any custom playing card meant for real gameplay. A thin sheet of black paper is laminated between two white printed sheets, then the sandwich is finished with linen or smooth coating. Hold a black-core card up to a lamp and you'll see no shadow of the face through the back — opponents can't 'read' the deck by spotting the dark mass of an Ace of Spades behind thin paper. Cheap promotional decks skip the black core to save cost, which is why they feel translucent and effectively unusable in poker or magic performance. Standard 300 GSM black-core is our most-ordered playing card stock; 310 GSM deluxe black-core adds a touch more rigidity and a deeper snap on riffles, preferred by magicians and cardists. Both ship with air-cushion linen by default. Black-core paper also takes ink slightly differently than uncored stock — colors print a hair more saturated because there's no light bouncing back through from the white reverse, which is why a black-core deck almost always looks richer than the same artwork on standard cardstock.