I was exploring the new snapshot when I noticed that a gold vein (block pictured is located at 148 -37 272, seed:-6596446101284927022) spawned as a regular gold ores instead of Deepslate variants, even though it was found much below y level -8. My assumption is that this was caused by the vein spawning in a Tuff deposit. It is unknown to me if this is recurrent for all iterations as I can only find the one instance of ores spawned in Tuff.

Edit:

Found more, and it appears ores just switch versions whenever encased in tuff, as half of the vein was Deepslated, the other half not.