Raynaud’s is a good warning sign for me. Only once have I ever had the absolute white finger, though. I generally notice it when my skin turns mottled and blotchy. I always have a good supply of hot hands to help.
I didn’t realize you’re a potter. Can you post pictures of your creations?
I have it too.
Mostly my middle finger on the right hand.
HATE it!
Soaking my hands in VERY warm water brings it
back to normal in a few minutes.
If I let my hands get cold in winter, it
gets really bad. that finger looks like it belongs on a corpse!