Mineshaft

Most of the time, mineshafts will generate in any overworld biome, usually underground and rarely in oceans. The structure is generated before chunk features like ores. Sometimes two or more mineshafts can generate close to each other, which will produce huge complexes.

Mineshafts sometimes intersect with canvas and canyons, and corridors of wooden planks are generated as a result. Sometimes bridges are also generated suspended over empty space. In badland biomes, mineshafts can sometimes generate on the surface; these have more gold ores at higher altitudes as compared to other biomes. You will find minecarts with chests throughout the mineshafts that contain items such as iron and gold ingots, rails, or seeds.

All mineshafts have the following structures:

Crossings: Crossings are dual floor 5x5 intersections that are supported by wooden columns.

Staircases: These are diagonal tunnels where stair blocks are not used.

Starting points: This is a 10x10 parlor with an arched ceiling. There are four exits; one in each direction.

A starting point with exits (via screenshot)

Corridors: Corridors are 3x3 tunnels and junctions which are supported by fences and wooden planks. Some places have cobwebs and some have torches on the walls. In long corridors, the fences used to support the tunnels are placed four blocks apart and sometimes will have missing plans which might have stones and cobwebs.

These tunnels have a rail system that is incomplete in some places. There will sometimes be minecarts with chests on the rail system, but they are a rare spawn.

Abandoned passageways: These are corridors with cobwebs that conceal cave spider spawners.

An abandoned passageway with a cave spider spawner (via screenshots)

Exploring a mineshaft can prove to be quite dangerous, so bringing the following items with you can help you loot the mineshafts while staying alive:

1. A sword preferably of iron or diamond in order to kill any hostile mobs.
2. An iron or diamond pickaxe to harvest ores you may find
3. Some milk to remove the poison effects caused by cave spiders
4. Dirt or cobblestone blocks to bridge gaps or block mobs.

These are some of the basic things you might want to take with you when exploring mineshafts.

The Bedrock and Java edition mineshaft chests can contain loot from 3 preset pools of items which contain the following:

1. Rails (78.4% chance)
2. Torch (65.7% chance)
3. Name tag (42.3% chance)
4. Glow berries (38.7% chance)
5. Bread (38.7% chance)
6. Golden apple (28.2% chance)
7. Coal (27.3% chance)
8. Beetroot seeds (27.3% chance)
9. Melon seeds (27.3% chance)
10. Pumpkin seeds (27.3% chance)
11. Iron ingot (27.3% chance)
12. Activator rail (27.1% chance)
13. Detector rail (27.1% chance)
14. Powered rail (27.1% chance)
15. Lapis lazuli (14.5% chance)
16. Redstone dust (14.5% chance)
17. Gold ingot (14.5% chance)
18. Enchanted book (14.1% chance)
19. Diamond (8.9% chance)
20. Iron pickaxe (7% chance)
21. Enchanted golden apple (1.4% chance)

A minecart with a chest (via screenshot)

Mineshafts were first added to the game in the pre-release beta of Java Edition v1.8. From v1.2.1 to v1.6.1 minor changes were made to them which made their construction more realistic and more immersive. By v.1.9, more loot was added to the loot pool along with rail tracks and torches.

From v.10, mineshafts could now spawn on the surface in mesa biomes, and by v1.18 more aesthetic changes were made to make the mineshafts more believable by adding chains and wooden arches to support the wooden corridors; all while constantly adding and diversifying the loot pool of the chests that spawn in the mineshafts.

1. All the chests that spawn in the mineshaft automatically turn into minecarts with chests that can either be on rails or on the floor.
2. In the early versions, the support beams were made of solid planks instead of wooden fences as they are now.
3. A rare glitch can cause a mineshaft to be generated floating in the sky when the preset “desert” is used for a super flat world.
4. All mineshafts have a companion cave that follows them.

Mineshafts are great structures if you are looking to explore and at the same time get rewarded for it. Once properly geared up you will be dealing with mobs easily and thus making the experience not too challenging.

Q. How to find mineshafts easily?

A. When exploring caves and ravines, look for wooden planks or cobwebs.

Q. Are mineshafts connected to caves?

A. Yes, mineshafts are often connected to natural caves.

Q. Do all mineshafts have chests?

A. No, chests have a random chance of generating, so they won't be there all the time.