Gravel Material Guide: Types, Sizes, and Which Stone to Choose
Walk into a landscape supply yard and you’ll face a dozen bins of stone with cryptic labels — ¾-inch minus, #57, crusher run, road base. This guide decodes the options so you can match the right aggregate to your project, then use the Gravel Calculator to order the right quantity of it. Choosing correctly matters: the wrong stone for a driveway means years of raking it back into place, while the right stone practically maintains itself.
How Gravel Is Classified
Aggregates are described by size (the sieve range the stones pass through), shape (rounded vs. angular), and gradation (whether fines are included). “¾-inch minus” means everything passes a ¾-inch sieve including the dust and small chips — the fines are what let it compact. “¾-inch clear” or “#57 stone” means the fines were washed out — it drains freely but won’t compact. That one word, minus vs. clear, determines whether the stone locks together or stays loose.
The Main Types
Pea Gravel (6–10 mm / ¼–⅜ in)
Small rounded stones, naturally smooth. The comfort pick for walkways, patios, playgrounds, and dog runs — easy on feet and paws. Doesn’t compact (rounded stones roll past each other), so it’s unsuitable for driveways. Needs firm edging because it migrates readily. Typical bulk density: ~1.4 tons/yd³.
Crushed Stone (20 mm / ¾ in, and #57)
Mechanically crushed angular rock. The ¾-inch size with fines (“minus”) compacts into a hard, load-bearing surface — the standard driveway and road-base stone. Washed #57 (no fines) is the drainage stone for French drains and septic fields. Angular faces interlock; this is the structural workhorse of the aggregate world.
Crusher Run / Road Base
A blend from dust up to ¾-inch or larger, designed to compact into something approaching pavement. Cheapest structural option; the dusty fines are a feature, not a flaw — they fill voids and bind the layer. Ideal as a base course under driveways, shed pads, and paver patios. Not decorative; usually topped with a cleaner stone where visible.
River Rock (25–150 mm / 1–6 in)
Large smooth stones prized for looks: dry creek beds, decorative borders, erosion control, water features. Sold at a premium per ton. Because pieces are big and irregular, coverage per ton is lower — allow extra depth so soil doesn’t show through. Also the classic French-drain stone in washed form.
Decomposed Granite (DG)
Granite crushed to sand-and-fine-gravel consistency. Packs firm with water and rolling for a natural, permeable path surface popular in dry climates. Can be stabilized with binders for higher-traffic areas. Tracks on shoes when loose; keep it out of entryways unless stabilized.
Recycled Concrete / Crushed Asphalt
Budget-friendly and eco-friendly base materials. Recycled concrete compacts well for driveways and base courses; crushed asphalt (millings) can re-bind in heat into a semi-solid surface. Availability varies by market. Fine for utility areas; check appearance if visible.
Matching Stone to Project
| Project | Best choice | Why |
|---|---|---|
| Residential driveway | ¾-in crushed or crusher run | Compacts, locks, bears loads |
| Garden path / patio | Pea gravel or decomposed granite | Comfortable, attractive |
| Decorative beds | River rock | Visual impact, low maintenance |
| French drain / drainage | Washed #57 or river rock | No fines = free drainage |
| Shed / structure base | Crusher run, compacted | Stable, level, drains |
| Dog run / play area | Pea gravel | Soft, drains, easy to clean |
| Xeriscape | Decomposed granite + rock accents | Permeable, natural look |
What to Ask the Supplier
- “Is it minus or clear?” — determines compaction vs. drainage behavior. The single most important question.
- “What’s the bulk density?” — the tons-per-yard figure for accurate ordering (see the formula guide). Most yards know this number.
- “Is it washed?” — washed stone is cleaner for decorative and drainage use; unwashed is fine (and cheaper) for base courses.
- “What quarry is it from?” — color and hardness vary by source; consistency matters if you’re matching existing stone or ordering in phases.
- “Minimum delivery?” — some yards have 2–3 ton minimums; know before you plan a small job.
- “Can I see it first?” — color and texture vary by quarry; a sample handful (or a visit to the yard) prevents surprises.
- “How is it loaded — bucket or weighed?” — weighed (scale) loads are exact; bucket-loaded “tons” are approximate. For large orders, weighed is worth asking about.
Quality Red Flags
- Excessive dirt or clay mixed in (weakens compaction, stains decorative stone, and indicates poor processing).
- Uniformly oversized or undersized pieces vs. the labeled gradation — a sign of inconsistent crushing or screening.
- For decorative stone: heavy color variation within one load (ask whether it’s from one quarry run; mixed sources look patchy).
- A strong odor or oily sheen — rare, but recycled materials can occasionally carry contaminants. Reject the load.
Storing Leftover Stone
Keep surplus on a tarp, covered if possible — uncovered piles grow weeds and collect debris, and stone mixed with soil is miserable to reuse. A half-ton leftover from a driveway project is next spring’s top-up material; stored properly, it’s as good in two years as the day it arrived. This is also why rounding up on the order is smart economics, not waste. If you have no space to store it, offer it to a neighbor — a wheelbarrow of free gravel is a universally welcome gift in any neighborhood with gardens.
Pricing by type is broken down in the cost guide, and installation technique in pro tips.
Related Guides
- Gravel Calculator: The Complete Guide
- Gravel Cost Guide
- Gravel Calculator: Pro Tips
- Gravel Calculator FAQ
- Gravel Estimating Guide
Choose, Then Calculate
Pick the stone for the job — angular for driveways, rounded for paths, washed for drainage — confirm the bulk density with your supplier, and run the numbers in the Gravel Calculator. Right stone plus right quantity is the whole game. And when in doubt between two similar products, choose the one your local supplier stocks consistently — availability for future top-ups matters more than small differences in appearance or price.
Disclaimer: Aggregate names and gradations vary by region and quarry. Confirm specifications with your local supplier; calculator results are planning estimates.
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