Tool

Tools are items used by the player while held to perform actions faster, to gather materials not obtainable by hand, or to perform completely new actions. With the exception of the clock and compass, tools do not stack in the inventory.

Diamond tools vs. Gold tools
Even though gold tools mine faster than diamond tools, Gold tools have a mere 33 uses. Compared to the 1562 uses of diamond tools, this is useless, making diamond tools better on the whole.

Trivia

 * If you switch from a more valuable to a less valuable tool, without releasing the mouse button, just before a block breaks, the time required will be similar to using the former tool, while the mined block will be counted against the latter's durability. This is true for shovels, axes and pickaxes. However, in the case of pickaxes, this only works if the latter can mine this type of block, e.g. for iron and stone pickaxe while mining iron ore it would work, but for diamond and iron pickaxe while mining obsidian it wouldn't. Profitable uses for this (in terms of time saved) are rare.
 * Jens told us around 1:30 in this video that it is going to be possible to upgrade your tools.

Werkzeuge Outils Narzędzia Инструменты