This can seem unuseful, but please keep reading.When you put fire or lava right next to a gold block (altough this can be extended to other metals), the gold would melt after a few minutes, like 1-2 minutes (melting times can be various with other metals). When molten, it would have the same flowing, burning and glowing properties lava has. It could be collected in Dwarven Buckets, and would become Dwarven Buckets filled with solid gold after a countdown of 25-30 seconds (can be useful for later ring forging). When unsmelted, the bucket with solid gold would give 3-4 gold ingots, the bucket staying in the unsmeltery slot.
EDIT : If you place a gold block in any existing forge, and a dwarven bucket with it, it would result in a molten gold bucket, as if you had collected it from molten gold. Thanks to The Desert Wanderer for making me thinking of it ^^
Molten gold would have a golden-orange glowing and animated texture. It would look great in great dwarven forges, with pools of molten gold glowing in the darkness.
EDIT (2) : See also this comment for a funny achievement.
Sagaert22 Amrod Last Son of Fëanor