Questions about melting ice blocks

I have three questions about ice blocks in Minecraft:

1. Do redstone torches melt ice?

2. Which light source melts ice the fastest?

3. Can packed ice melt?

3

1 Answer

1. No.
2. Ice melts if the light source around it is greater than 11. There is no way to speed it up; it either melts or it doesn't. It's completely binary.
3. No.

Sources -

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