Short answer
Crackstone can only be broken with an advanced digging tool. The official Crackstone page states that the Shovel and Gun do not affect it, while other digging tools can destroy it. When Crackstone breaks, nothing remains, so do not approach it expecting a material drop or a hidden recipe.
Why the first tools fail
Crackstone is a hard material, not a normal Sandustry resource node. The source lists it as having a single point of health, but the important player-facing rule is tool compatibility: a low-tier excavation tool is not enough. Repeatedly swinging the Shovel or firing the Gun at the same tile will not turn the block into a resource and will not progress the route.
That limitation is useful information about progression. If a Crackstone wall blocks a path, the correct response is to continue the Research and tool progression until an appropriate digging tool is available. The Beginner’s Guide treats Research as the system that unlocks new tools and buildings, so the wall is a signal to improve your tool access rather than a puzzle solved by brute force with the starter kit.
A safe clearing sequence
First, identify the material as Crackstone rather than assuming every dark or solid tile has the same rule. Next, check the current tool you have equipped. If it is the Shovel or Gun, move on; the official entity page explicitly excludes both. When you have another digging tool available, use it on the Crackstone and confirm that the tile is removed before planning a long factory line through the space.
The source says all other digging tools will destroy Crackstone, but it does not provide a permanent unlock cost or a universal timing for the required tool. Those details can change with Research tuning. This guide therefore does not invent a cost, a minute mark, or a recommended speedrun route.
What you receive after breaking it
Nothing remains after Crackstone is destroyed. That means the benefit is access: a cleared route, a more usable building area, or an opened line of sight. It is not a mining step that should be added to a production calculation. Keep the distinction clear when planning storage or conveyors; there is no Crackstone output to route into a Shaker, Filter, or other building.
Troubleshooting
If the block does not break, check the tool first. The documented failure case is using the Shovel or Gun. If you are using another digging tool and the behavior differs from the official page, treat that as a version check rather than a reason to guess a new recipe. Record the current build, test the behavior in a small safe area, and compare it with the official Wiki before publishing a screenshot or a new numeric claim.
Crackstone is a small example of how Sandustry’s destructible world works: the terrain is physical, but not every tile is a resource. Some surfaces ask for a later capability and then simply disappear. Follow the tool progression, preserve your factory layout until the path is confirmed, and remember that this page answers the tool question only; it does not claim a universal map location for every Crackstone wall.