Buttermilk is described as an "opaque pale yellow"
Testers reported "Buttermilk is a lovely neutral coloor. The bead on the left has a small wrap of Double Helix Terra which was reduced just a bit. The Terra didn’t react with the base colour except to fume it just a tad"
"Buttermilk was engineered in response to requests for a
replacement for Cake Batter [now sold out] or a similar
pale opaque yellow"