Add electronic devices designed for professional miners, including:
portable geothermometer that shows temperature variations
of solid blocks (water and lava affect block relative temperature
- water cools it down while lava warms it up; useful for underground
mining to search - or avoid - flooded caverns or lava pools);
mineral scanner - shows all ores in area around player, selectable
range; mineral finder - short range directional scanner to find
nearby deposits of selected mineral; 3-in-1 versions of above
devices with improved characteristics.