I was surfing the net this morning and found this supplier in UK. They have a couple of videos that were really well made. This is mainly for new comers who have questions on tapping and carbide inserts. But, I will confess, I never heard anybody compare carbide insert composition to Rice Krispies!
https://www.youtube.com/channel/UCiJnCB7xMOktKSCm9ACngpw/featured
https://www.youtube.com/channel/UCiJnCB7xMOktKSCm9ACngpw/featured