The ocean monuments from the Release 1.8 Minecraft update introduce 4 new blocks (prismarine, prismarine bricks, dark prismarine, and sea lantern), 2 new mobs (guardians and elder guardians), and 2 new items (prismarine shards, prismarine crystals). You can use these items to craft 3 of the 4 new blocks.
What is a natural levee and how is it made? -Natural Levees are formed by the river in its process of flooding -A natural levee is formed by a deposit of sand or mud built up along, and sloping away from, either side of the flood plain of a river or stream.
Human made levees, such as we see on the Mississippi River along much of its length, are much higher and are constructed to prevent flooding from high discharges on the River. Most levees are constructed of piles of dirt (rock and soil) with a concrete cover on the river side of the levee.