Copper Bulb is a toggleable light-emitting block crafted from copper, redstone, and a blaze rod. Unlike redstone lamps, copper bulbs do not require constant power—a single redstone pulse turns them on or off permanently until the next pulse. This makes them efficient for compact lighting systems or logic circuits.

The brightness of a Copper Bulb depends on its oxidation stage. Fresh copper bulbs emit the maximum light level of 15, while oxidized bulbs emit less. You can stop oxidation by waxing the bulb with honeycomb. Bulbs can also be scraped with an axe or struck by lightning to reverse oxidation.

Copper bulbs are compatible with redstone components like comparators and observers. A comparator reads 15 signal strength when the bulb is lit and 0 when unlit, allowing it to act as a redstone memory cell or state indicator. Observers detect when the bulb receives power, enabling pulse-based automation setups.

They can be waterlogged, emit no light when off, and serve as stylish alternatives to redstone lamps in both industrial and steampunk-themed builds.