What format is an Android lollipop sd card?

[AC Question]

I have a Blu Tank ii dumb phone. I put my android sd card in it from another phone. It worked. Then I formatted the card so I could see how the dumb phone formatted the directory structure, so I would know where to add music.

I have formatted the card as Fat32, Exfat, and NTFS, and my Blu Tank ii dumb phone still doesnt' recognize the sd card.