In Minecraft plugin yml files like config.yml, how would I give something's nbt display a color?

Like something like this:

   '1': '{"type":"DIAMOND"} {"type":"IRON_INGOT"} {"type":"DIAMOND"}'
   '2': '{"type":"DIAMOND"} {"type":"REDSTONE"} {"type":"DIAMOND"}'
   '3': '{"type":"AIR"} {"type":"AIR"} {"type":"AIR"}'
   craft: '{"type":"DIAMOND_PICKAXE","enchantments":[{"type":"LOOT_BONUS_BLOCKS","level":2},{"type":"PROTECTION_PROJECTILE","level":1},{"type":"PROTECTION_FIRE","level":1},{"type":"PROTECTION_EXPLOSIONS","level":1},{"type"}]}'