Polished Blackstone Brick Slab

Overview

Polished Blackstone Brick Slab is a Nether block in Minecraft Java Edition 1.21.4. A crafting table turns its ingredients into Polished Blackstone Brick Slab. Its hardness of 2 makes it a normal, unhurried block to mine.

Anything below a wooden pickaxe breaks it without leaving a drop. It drops as the same block you mined. It stacks to 64.

You make it with Polished Blackstone Bricks. You can also cut it from Blackstone on a stonecutter. It is not used in any crafting recipe.

How long it takes to break

Polished Blackstone Brick Slab has a hardness of 2. By hand that is 10 seconds per block; with the correct tool at netherite tier it is 0.35 seconds.

You are looking at 0.5 seconds on iron and 0.4 on diamond — the iron step is where the time actually falls.

A weaker tool still breaks it, but anything under wooden returns nothing — you spend the time and lose the drop, which is how most veins get wasted.

Efficiency contributes its level squared plus one to tool speed, which makes Efficiency V roughly 3.5 times faster than the plain tool.

* breaks the block but yields no drop
Tool	No enchantment	Efficiency III	Efficiency V
Hand *	10 s	10 s	10 s
Wooden	1.5 s	0.25 s	0.15 s
Stone	0.75 s	0.25 s	0.1 s
Iron	0.5 s	0.2 s	0.1 s
Diamond	0.4 s	0.2 s	0.1 s
Netherite	0.35 s	0.2 s	0.1 s
Golden	0.25 s	0.15 s	0.1 s

Properties

Blast resistance on Polished Blackstone Brick Slab is 6, so an explosion nearby will usually take it out. It stops light entirely and gives off no light. Stack size is 64 — the standard full stack. The block is tagged for pickaxes, and only that class gets the speed bonus; everything else mines at bare-hand rate.

Transparent: No
Required tool: Wooden Pickaxe