How do I unlock the stone category in Little Alchemy 2?

In Little Alchemy 2, the Stone category is not something you "unlock" in the traditional sense. Instead, you create the Stone element by combining specific basic elements. Here's how you can make Stone:

1. Start with the basic elements: Earth and Fire.
2. Combine Earth and Fire to create Lava.
3. Combine Lava with Air to create Stone.

Once you have created Stone, it will be added to your collection, and you can use it to create other elements in the game. The Stone category will naturally become available as you progress and discover more elements that involve Stone in their combinations.

If you're looking to track your progress or see what elements you've created, you can use the in-game encyclopedia, which lists all the elements you've discovered and hints for those you haven't. This can help you stay organized and focused on finding new combinations.

Good luck, and happy alchemizing!