We (and many other herbaria) use a different color chip so it would be nice to have a way to recognize different color chips.
See this image for an example of one used by BRIT:
https://bisque.cyverse.org/image_service/image/00-Bu6svkTKkNx5hdB8niSokV/resize:4000/format:jpeg
It is a ColorTrax 2x3 card that has been cut down the middle
https://www.cameratrax.com/color_balance_2x3.php