Exposed Copper Bulb

The exposed copper bulb is a new light-emitting block introduced in Minecraft 1.21, the 'Tricky Trials' update. It toggles on or off when it receives a redstone pulse and does not require continuous power to emit light. Its light level depends on the state of oxidation of the copper. Unoxidized copper bulbs emit the brightest light, while the intensity decreases as the oxidation increases. Exposed copper bulbs will oxidize over time, changing from their initial copper color to green. To prevent oxidation, exposed copper bulbs can be turned into waxed exposed copper bulbs with honeycomb, preserving their original color and brightness. Players can craft 4 exposed copper bulbs at a time by using 3 exposed copper blocks, 1 blaze rod, and 1 redstone dust in a crafting table. Waxed exposed copper bulbs require waxed exposed copper blocks instead. Exposed copper bulbs can naturally generate in trial chambers. Mining copper bulbs with a stone pickaxe or better will yield a drop; otherwise, nothing will drop. A redstone comparator can read the state of a copper bulb and output a redstone signal based on whether it's lit, making it usable as a compact T flip-flop.