Save up on Rubies. They're not only good for the Sacrificial Meter, but you'll never know when you'll be far away from the main altar and need to sacrifice.
If you don't prefer building all of the Building Plot Makers and Altars, then sacrifice them or get three of them to make a MaxHunger Potion in a Alchemy Station.
Trivia[]
Rubies are the only ore that can be used in the Alchemy Station. [as of right now]
A ruby's "rarity" is often as rare [if not, rarer] as a Sapphire.