#89 Stone vs Lava Rock: Size, Cost, and Which to Use

#89 Stone

In the ASTM C33 sieve table, #8 stone passes a 1/2-inch screen and stays on a #8 sieve (about 3/32 inch), and #9 is a step finer. #89 is a blend of the two: most of it passes a 3/8-inch screen and stays on a #16 sieve. In practice you get a clean, small, sharp stone that looks like crushed pea gravel. Some quarries sell the same product as #8, #9, or "3/8 clean."

Lava Rock

Lava rock is a lightweight, porous volcanic stone commonly used in landscaping. Its rough texture helps retain moisture while allowing airflow to plant roots.

#89 Stone

• ✓ Walkways
• ✓ Patios
• ✓ Pipe bedding
• ✓ Asphalt mix
• ✓ Dog runs
• ✓ Driveway top dressing

Lava Rock

• ✓ Landscaping
• ✓ Garden beds
• ✓ Decorative ground cover

#89 Stone

• + Packs firmer than pea gravel at the same size
• + Stays put inside edging
• + Wheelbarrow and stroller friendly
• + Clean, so it drains
• + Cheap at $22 to $40 per ton

• − Plain gray look
• − Sharp edges, not for bare feet
• − Too small for a driveway surface
• − Less void space than #57 for drainage

Lava Rock

• + Very lightweight
• + Excellent moisture retention
• + Decorative appearance

• − Breaks down over time
• − Sharp edges
• − Can scatter easily

#89 Stone

#89 stone is crushed stone screened to about 3/8 inch and smaller, with most pieces between 1/8 and 3/8 inch and no dust. It is angular, a blend of the #8 and #9 sieve sizes. Color follows the quarry: gray or white limestone, gray to pink granite, or dark basalt.

Lava Rock

Typically 3/4"–1.5" sizes. Red or black.