Polished Blackstone Slab — Minecraft block

Overview

In Minecraft 1.21.4, Polished Blackstone Slab is a Nether block. Polished Blackstone Slab is made at a crafting table. Hardness 2 puts it in the middle of the pack for mining speed.

Mine it with a wooden pickaxe or better, or you get no drop at all. Broken correctly, it drops itself. Sixty-four fit in one inventory slot.

The recipe calls for Polished Blackstone. A stonecutter can cut it straight from Blackstone, with nothing wasted. It goes into exactly one recipe: Chiseled Polished Blackstone.

How long it takes to break

Polished Blackstone Slab sits at hardness 2: 10 seconds per block with your fists, 0.35 with the correct netherite tool.

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.

The Efficiency formula is level² + 1 added to tool speed — at V that is about 3.5 times the unenchanted rate.

* 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 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. A pickaxe is the fastest choice here. A tool of the wrong class is no better than your fist — the speed bonus is tied to the block's own tool tag.

Transparent: No
Required tool: Wooden Pickaxe