Stone Dust
Stone dust — also sold as screenings or #10 — is crushed stone a quarter inch and finer that packs hard when compacted; a ton covers about 120 square feet at 2 inches deep.
Work out what you need
Measure the area, set the depth, and this converts it to cubic yards, what it weighs on the truck, how many bags that replaces, and roughly what it should cost delivered.
Weight is quoted as a band because moisture moves it more than grade does — stone dust after heavy rain runs to about 115% of its dry weight. The delivered range starts from a published $25–80 per cubic yard and is scaled by how your region's material prices compare with the national average, so treat it as a sanity check and not a quote.
Get a real price from yards near youWhat stone dust is good for
Crushed stone a quarter inch and finer, fines included — sold as screenings, quarry dust or #10. It packs hard when compacted and drains slowly because of it. That is what makes it useful under flagstone and on paths — it locks the stone in place and gives a firm, walkable surface over a compacted base. It is the wrong choice anywhere water needs to pass through.
As a paver bedding layer it holds water and its fines wash out from under the joints; the paver industry specifies washed concrete sand there instead.
Stone dust vs sand
| Stone dust | Concrete sand | |
|---|---|---|
| Drainage | Slow — the fines hold water | Fast — washed sand drains |
| Compaction | Packs firm, almost crusty | Settles but stays loose |
| Paver bedding | Not recommended by the paver industry | Specified: washed concrete sand |
| Flagstone and paths | Good — holds stone in place | Shifts more underfoot |
| Cost | Usually among the cheapest things a quarry sells | Similar, varies by region |
Stone dust questions
What is stone dust?
The fine material left over from crushing stone, a quarter inch down to powder. Depending on the yard it is sold as stone dust, screenings, quarry dust, crusher fines or #10.
Does stone dust get hard?
It packs firm when it is wetted and compacted, and can form a crust — but it is not concrete. It does not set, and under traffic or standing water it ruts and softens.
Is stone dust better than sand under pavers?
For the bedding layer, no: the paver industry specifies washed concrete sand, because stone dust holds water and its fines migrate out through the joints. It is common practice in some regions anyway.
How much stone dust do I need?
About a ton for every 120 square feet at 2 inches, or 235 square feet at 1 inch — the usual depth when it is a setting layer under flagstone.