In Terraria 1.0.6, in the underworld (eg, hell):
- ash no longer falls down when unsupported
- mining a hellstone block produces a block of lava
- you can no longer place bricks where lava is - previously this could be used to "block over" lava pools, to dry them up or tunnel through them
What's are some good (or efficient) mining techniques for :
- mining hellstone?
- creating navigation tunnels?
- for crossing chasms of lava?
In light of the changes? We have this question How do I mine safely in the underworld without Ash falling on me? but it no longer applies with the updates.