Sea Lantern

Sea lanterns are underwater light sources that appear in ocean monuments and underwater ruins.

Breaking
A sea lantern can be obtained only when mined with a tool enchanted with Silk Touch. When broken using anything other than a Silk Touch enchanted tool, it drops 2–3 prismarine crystals. The Fortune enchantment increases the number of prismarine crystals dropped. This method of obtaining sea lanterns is wasteful though; the 4 prismarine shards and up to 3 of the prismarine crystals used to craft it are non-retrievable.

Each level of Fortune increases the maximum number of prismarine crystals dropped. The amount is capped at 5, so Fortune III simply increases the chance of getting 5 crystals.

Natural generation
Sea lanterns generate throughout ocean monuments, as well as in some ocean ruins.

Light source
Sea lanterns emit a light level of 15, the brightest possible light level in the game. They produce the same amount of light as glowstone, redstone lamps, jack o'lanterns, lanterns, beacons, conduits, and shroomlights.

Conduit power
Sea lanterns can be used to activate a conduit by building a structure around it. By doing this, the conduit emits the Conduit Power effect in a certain radius, depending on how many blocks are used to power it. Prismarine, dark prismarine, and prismarine bricks can also be used for this purpose.

Note Blocks
Sea lanterns can be placed under note blocks to produce "Clicks and Sticks" sound.

Opaque block
The Sea Lantern is an odd block when it comes to transparent block behavior. Like a transparent block, it won't block the opening of chests, monsters (including Slimes) won't spawn on it, and it doesn't transfer a redstone signal. However, unlike transparent blocks, players and mobs will suffocate inside it, and it will block a Beacon beam, preventing the Beacon's activation.

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