Kind of surprised no one has mentioned frost resistance mead. If you prop them up using item stands they emit some blue light. It's more faint than a torch, but it's an option if you want an all-blue lighting build. Making 10+ frost resist mead shouldn't be that expensive, not to mention the light wouldn't require any refilling, however it doesn't seem like enough light to light up a whole room in the dead of night.

Originally posted by jemYZX:

Originally posted by Grandaddypurple:

Sconce only come with the normal fire color for now. Standing blue torch is the only blue source for now

I think you haven't gotten far.

There's "plain wood", "iron", "blue flame", and "green flame" torch stands.

Then there is just "Plain Copper Sconce". (Depending on a future update for more Sconce varieties)

We shall wait.

The person you're responding to specified sconce.