This is a bit of a misunderstanding on the part of NileBlue: the NIST materials are not pure; they are produced mostly normally. The only reason they are expens

This is a bit of a misunderstanding on the part of NileBlue: the NIST materials are not pure; they are produced mostly normally. The only reason they are expensive is that, once prepared, very precise measurements have been done on them, available along the purchase, so that food manufacturers can calibrate their machines. Here’s a video talking about that: https://youtu.be/YqYAWF7wd9k?si=OeNMVoU66ZvQUts7&t=658 https://youtu.be/YqYAWF7wd9k?si=OeNMVoU66ZvQUts7&t=658