Ice

Ice is a translucent solid block formed in snowy Biomes (formerly winter worlds) from exposed water, and is slightly slippery. Ice blocks can be obtained using any tool with the silk touch enchantment.

Ice can be easily destroyed without tools, but the use of a pickaxe speeds up the process. If there is another block directly underneath the ice block, it will revert to water when broken. If not, it will shatter without producing water. Due to its transparency, ice cannot have Torches placed on it directly. However, even though ice is non-transparent in Pocket Edition, torches still cannot be placed on it.

When a slab is placed on top of ice, the slab has the same "slipperiness" as the ice below it. This applies to every other block with a hit-box that is lesser than a full block. (This does not work in Pocket Edition with slabs, but does with the closed trapdoors.)

Ice will also melt into water if the light level immediately next to it on any side is sufficiently high (greater than 11), from light sources other than sunlight. Conversely, a water block in a snowy biome will eventually freeze into ice if exposed to the sky from directly above, and the light level immediately adjacent to the water block on all sides is sufficiently low (less than 13). This can happen at any time of day, and in any weather condition. If the highest adjacent light level is 12, an ice block will alternately melt and re-freeze when it receives a block tick.

Items and broken blocks move extremely fast when in water that is flowing over ice. This is particularly useful for transporting resources using water currents because items will keep sliding on ice blocks when they are dropped at an angle, even if water is not placed on top. However, as stated before, light melts the ice, and if there are no torches around a zombie could sit there and pick up your precious items. However, Packed Ice is melt resistant. It is non renewable, but this shouldn't be a problem since it comes in huge quantities.

Potential uses

 * The repeated thawing and freezing at light level 12 can be used to make a redstone noise generator. Use a BUD to catch the random events.
 * If creating a water slide, ice blocks can be used as the bottom pieces of the slide to speed up item movement.
 * Because items exiting a water flow will continue to slide on up to two blocks on ice, sequences of flowing water over ice can be used to transport items indefinitely with no vertical drop necessary.
 * Items that exit water flowing over ice can slide up to nine blocks on ice.
 * The player can use Silk Touch to collect ice blocks and place them in the Nether. However, they don't make water when broken or melted.
 * Making a 2-block high hallway with an ice floor, and trapdoors above the ice then sprint-jumping down it causes the fastest possible speed in the game. However, this will rapidly deplete the player's hunger bar.
 * The player can build structures with ice in a tundra biome by putting dirt (or any other blocks) around the walls that will be built. After the player lays out one level of dirt, the player can pour water into the layout with buckets until all blocks have become ice. After this, make another level and repeat. There should be no blocks anywhere above the block of water the player wants to freeze, since water will not freeze with blocks directly above it.
 * When placed on ice, Cobweb's & Soul Sand's slowing effect will be greatly increased. This makes it helpful for live capture traps.
 * Ice can be used as a stackable water source.
 * The player can build structures with ice floor so items slip from 6-8 blocks away when thrown, this can be used to play "mini golf" by throwing items and trying to get them into a specific block, such as holes or any other block different than ice such as a hopper.
 * Ice blocks behind other ice blocks are invisible. This makes for a great ice maze. Other items that don't show behind ice are water and lava. However, if lava is one block away from the ice, the ice will melt into a water block.
 * If you get into just the right position, then sprint over around 5 ice blocks, you can jump 4 blocks across a pit.

Farming Ice
Ice can be obtained in survival mode with a Silk Touch enchanted pickaxe, which allows ice to be farmed. Contraptions can be made which constantly create infinite water sources. This would have to be done in a snow biome in order for the ice to replace the water source blocks.

Trivia

 * If a player rides a pig on ice using a saddle, the pig moves incredibly fast, making journeys across long frozen lakes easier.
 * By sprinting and jumping while on ice and inside a 2-block tall tunnel, it is possible to move 16 blocks a second, twice as fast as a full-speed minecart. By replacing the 2-block ceiling with trapdoors, it's possible to travel 1000 blocks in 54 seconds, or 18.518 blocks per second. However, this will drain the player's hunger bar extremely quickly at roughly 1 unit per second.
 * Ice isn't as translucent as glass, so light passes through ice blocks diffusely, reducing the light level by 2 per ice block.
 * Along with Portals, Stained Glass and Water, Ice is one of the few blocks that uses translucent pixels (colored but still semi-transparent) in the default Minecraft texture pack.
 * It is possible to see the edges of chunks through ice, but only in "Fast" graphics setting.
 * Sugar cane can be found next to ice, though when updated they will drop as items. This can be observed at random when running through a snowy biome.
 * If you try to light ice on fire with a flint and steel no flames will appear, but the flint and steel will still act as if it had been used (its durability will decrease slightly). The same thing happens with glass and the sides of non-flammable blocks.
 * If an ocean biome is beside a snow biome, "ice shelves" may be formed.
 * If the user is playing on a non-snow Alpha map generated before the Halloween update, oceans may freeze over because of ice regeneration in the newly generated snow biomes.
 * Water can only freeze if there is at least one horizontally adjacent non-water block. This makes ponds, rivers, etc. freeze from the edges in to the middle.
 * Ice is not transparent in Pocket Edition. However, items/blocks that cannot be placed on transparent blocks such as ice (i.e. torches) still may not be placed.
 * Mobs can not spawn on ice.
 * If a chest is placed on ice, it will have the same slippery effect as ice.
 * If an ice block is melted by a light source, it will not cause a block update. This can be used to make "floating" water blocks without signs, ladders, pressure plates, etc.

Gallery
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