"white card" is correct and usable in written English.
You can use it as a noun to refer to a card that is white in color. For example, "I found an old white card among my mother's belongings."
His white card read, "Cards Against Humanity".
All but the judge drop a white card face down into a pile.
So we all wait silently for a "white card," authorization to travel outside Cuba.
Customers receive a plain white card that can be used like a debit card.
On each door was a slot holding a white card with a name printed on it.
8. To create your mount, take a piece of thick, textured white card.
His almost mythic name, Zlatan Ibrahimovic, is written on a white card in ornate black lettering.
If you support management, sign the white card, which lists only its candidates.
A white card with the number eight was taped to the outside.
Where there were narrative gaps, Mr. Lapine put a blank white card.
But Peters said he was confident teams would not abuse the white card system to gain an unfair advantage.
