Minecraft resource gathering/Emerald

Introduction
An emerald is a rare mineral in Minecraft added to the game in snapshot 12w21a of version 1.3.1 of the game. Emeralds should not be confused with the diamonds, that were added in the indev version of the game and at that time were referred to in the code as emeralds.

Trading
A very common speedrunning technique to getting emeralds is using a fletcher for stick trades. The fletcher will request 32 sticks and will offer 1 emerald. To get a fletcher you will need to put 4 blocks of wood in a crafting table just as you would to craft a crafting table and two flint above the wood and place the fletching table beside a villager that doesn't have a job/profession. There is a chance that it won't give you this stick trade, but all you have to do is break the fletching table and re-place it. Another method to trade for easy emeralds is to use glass panes for emeralds on a librarian to get emeralds.

Mining
When mining an emerald ore using an iron pick or a better one, one emerald will drop, assuming that the pickaxe is not enchanted with fortune. If it is, it may or may not drop an extra emerald per every level of fortune. The maximum level of a fortune enchantment is Fortune III, thus the maximum amount of emeralds that can be dropped by an ore is 4. If you mine an emerald ore using a silk touch pickaxe, you will get the ore block instead of an emerald.

Crafting
A block of emerald (which is crafted by putting 9 emeralds in a crafting table can be uncrafted to 9 emeralds. In single player, you won’t find emerald blocks lying around, but in multiplayer you can receive them from other players.

Smelt
You can receive emeralds by smelting an emerald ore in a furnace, however this probably isn’t the smartest option, since that will require using fuel. If you have emerald ores in you inventory that you wish to convert to emeralds, you can just place them on the ground and mine them with a pickaxe. If for whatever reason, you don’t have a pickaxe, you can smelt them using any fuel.

Structures
Emeralds can be found naturally generating in chests in the following structures:
 * Buried treasure
 * Desert temple
 * End city
 * Igloo
 * Jungle temple
 * Shipwreck
 * Underwater ruins
 * Village (inside the chests of some of the houses)

Mob drops
If a fox that is holding an emerald dies, it will always drop the emerald. You can convince the fox to drop the emerald without killing it by throwing food items on the ground near it.

Vindicators and evokers may or may not drop an emerald upon death. If killed via a weapon enchanted, the maximum amount of emeralds increases by one per every level of the enchantment. If using a sword enchanted by enchantment III, the maximum number of emeralds dropped is 4.

Currency
The main use of emeralds in Minecraft is as a currency. They can be used to buy items from villagers and wandering traders.

Beacon
Another use of emeralds is to select powers from a beacon. The player should choose a power from the ones available and then put an emerald in the slot. Emerald blocks can also be used to make the pyramid below the beacon.

Java Edition 1.3.1
Emeralds and emerald ore were first added to the game in snapshot 12w21a of version 1.3.1 of the Java Edition of the game. Players can trade the emeralds for different items with the villagers. The same snapshot added desert temples, which have a hidden chest room containing emeralds, along with other resources. During development, rubies were meant to be used for trading, though they were replaced with emeralds before snapshot release. The unused ruby texture however can be found in the game file of this version.

Blocks of emerald were added in snapshot 12w22a, the same snapsnot that also added jungle temples. Jungle temples contain emerald in their loot chests.

Java Edition 1.4.2
Snapshot 12w32a added zombie villagers that can spawn naturally. It’s possible to cure a zombie villager, and it will become a regular villager. That means emeralds can obtain/use emeralds in trades even if he turned off structure generation in the world settings.

Java Edition 1.9
Snapshot 15w31a added end cities that contain end ships. Emeralds can be found in the end ships.

Snapshot 15w43a added igloos, that have basements with loot. Emeralds can be found in the chests in those basements.

Snapshot 15w44a increased the number of emeralds that can be found in a dessert temple.

Java Edition 1.11
Vindictators and Evokers were added in snapshot 16w39a. If killed by a player, they will drop emeralds.

Java Edition 1.13
Snapshot 18w09a added Ocean Ruins. Ocean ruins contain loot chests which may include emeralds.

Snapshot 18w10a added buried treasure. Emeralds may generate in the chests of buried treasure.

Java Edition 1.14
Snapshot 18w43a changed the textures of emeralds. In the same snapshot, pillagers were added to the game and at the time they were able to drop emeralds.

In snapshot 18w46a, pillagers stopped dropping emeralds.

Starting from snapshot 18w48a, emeralds can be found in chests in village tanneries, fisher cottages and plains village houses.

Snapshot 18w49a added emeralds to chests in other village house as well: shepherd houses, mason houses, butcher shops, and savanna and snowy village houses.

Snapshot 18w50a added emeralds to village fletcher houses, temples, desert and taiga village houses as well.

In snapshot 19w07a foxes were added to the game. They can sometimes spawn with an emerald in their mouths.

In snapshot 19w08a, the texture of emeralds was changed again.

Java Edition 1.17
The ruby texture which was not used anywhere in the code was removed from the game.

Pocket Edition Alpha v0.9.0
Emeralds were added in build 1 of the version, and blocks of emerald were added in build 5.

Pocket Edition Alpha v0.13.0
Desert temples were added in build 1 of this version. They can be found in the biome “desert hills”. Their chests contain emeralds, as well as other items.

Pocket Edition Alpha v0.15.0
Jungle temples were added in build 1 of this version. They contain emeralds in their loot chests.