Sandstone doesn't have a single Mohs hardness. It's a sedimentary rock composed of sand grains cemented together. The hardness of sandstone depends on:

* The mineral composition of the sand grains: Quartz is very hard (7 on the Mohs scale), while feldspar is less hard (6).

* The type of cement: Calcite cement is softer than silica cement.

* The degree of compaction and cementation: Well-compacted and cemented sandstones are harder than poorly cemented ones.

Generally, sandstone falls somewhere between 5 and 7 on the Mohs scale.

Here's a breakdown:

* Soft Sandstone: May be as low as 5 on the Mohs scale, meaning it can be scratched with a steel knife. This is usually due to softer sand grains and weak cementation.

* Medium Sandstone: Typically around 6 on the Mohs scale, can be scratched with a steel file but not a knife. This is common with a mix of quartz and feldspar grains and moderate cementation.

* Hard Sandstone: May approach 7 on the Mohs scale, being harder than a steel file. This occurs with mostly quartz grains and strong silica cementation.

It's important to note that even within a single sandstone formation, hardness can vary depending on location and geological conditions.