Tutorials/Mining specific blocks

Granite, andesite, and diorite
Veins of these blocks often yield more than a full stack. They can be found anywhere in the stone.

Gravel
Gravel can be found anywhere in the Overworld or the Nether (but it is more common in the Overworld). Go underground to find gravel because on the surface, it is only found next to water (the exception is next to cliffs or caves).

Ores
These are the ideal levels for mining the different ores. Levels are given for the player's head height (the level shown on the debug screen).

Lava
Lava is usually found in caves near the bedrock layer. It can also be found in the Nether.

Obsidian
Obsidian can be created by letting water flow over lava. This rarely occurs naturally, but can be manually caused. If you are building a nether portal, you can make the obsidian in the shape of a portal, making it possible to create a portal without a diamond pickaxe. Obsidian can also be found in the End.

Stone and similar blocks
Stone makes up most of the over world underground. However, the block varies depending on the dimension.