Minecraft wiki entry for Terrain_features, associated text: Bee nests: Generate on a small amount of oak and birch trees in various biomes, containing three bees.
Blob: Blobs of a certain type of ore or mineral.
Disks: Small circular patches of clay, sand, and gravel found underwater.
Ore vein: A long streak of ore and rock.
Spring: A water or lava source block that generates on the side of a hill, cave or ravine.
Random patch: naturally generating clusters of plants or fungi such as grass, ferns and flowers.
Forest rock: Boulder made entirely of mossy cobblestone found in giant tree taiga.
Ice spike: tall spires made of packed ice found in the ice spikes biome.
Iceberg: hill-like ice structures made out of ice, blue ice, packed ice, and snow found in frozen ocean.
Dripstone cluster: Stalagnate composed entirely of dripstone blocks.
Amethyst geode: Geodes of amethyst also consist of calcite and smooth basalt as outer layer found underground.
Leaf clay: clay patches with dripleaves found in lush caves, has dry and pool variant, pool variant looks like a pond.