Black Lava Rock (3/8")

Black Lava Rock (3/8"): Properties, Uses, and Key Information

Black Lava Rock (3/8"), also known as Black Volcanic Rock, Black Cinder Rock, Lava Gravel, Volcanic Cinder (when small), or Scoria (for the porous type), is a decorative, lightweight aggregate sourced from volcanic regions. This material consists of irregular, angular fragments, each approximately 3/8 inch (about 9-10 mm) in size. Its color ranges from deep black to charcoal, sometimes showing hints of dark gray. The rock is highly porous, non-toxic, and inert, making it suitable for a wide range of landscaping and decorative applications.

The rock's porous structure and low bulk density (about 40-50 lbs per cubic foot) provide excellent drainage and heat resistance. It does not decompose, break down, or fade in sunlight. Black Lava Rock is typically washed or screened to remove fines, but some dust may be present when dry. The pH is neutral to slightly alkaline, generally between 7 and 8, and the material is free of organic content. It is sold in bulk or bags, commonly in sizes of 0.5 cubic foot, 1 cubic foot, or larger. No ASTM or AASHTO standards are typically specified for decorative rock.

Main Characteristics of Black Lava Rock (3/8")

• Porous, lightweight, and irregularly shaped
• Dark black to charcoal color, colorfast under sunlight
• Non-combustible and highly heat resistant
• Good drainage properties, does not decompose
• Size: approximately 3/8 inch (9-10 mm)
• Non-toxic, inert, and free of organic material

Common Applications

• Decorative landscape mulch and ground cover
• Fire pit and fireplace media
• Drainage layers in planters and pots
• Walkways, garden paths, and tree rings
• Xeriscaping and drought-tolerant gardens
• Light-duty erosion control
• Gas grill and BBQ rock
• Some aquascaping uses (with caution due to possible pH changes)

Practical Details and Limitations

Black Lava Rock (3/8") is mainly used as a decorative material. Its lightweight and porous nature make it easy to handle and spread. The angular shape helps it stay in place on flat surfaces, and its dark color provides strong contrast against green plants and lighter paving materials. This rock is often selected for its natural, earthy appearance and ability to create visual interest in outdoor spaces.

However, this product has important limitations. It is not suitable for high-traffic driveways or heavy vehicle areas, as it can crush under weight. It is not recommended as a structural base material. The rock may not be appropriate for all aquatic environments, as it can alter water pH or mineral content. It is not suitable for playground surfacing due to its abrasive texture and lack of impact absorption. Black Lava Rock may increase soil alkalinity, so it is not ideal as a soil amendment for all plants. It can be dusty when dry, and is not ideal for use where fine dust is a concern. On steep slopes, the rock may migrate or wash away due to its light weight.

Comparison Table: Black Lava Rock vs. Other Materials

Installation and Usage Guidelines

For best results, prepare the area by removing debris, weeds, and loose soil. Grade and compact the underlying surface to ensure proper drainage and stability. Install landscape fabric under the lava rock to help prevent weed growth. Spread a 2 to 3 inch layer of Black Lava Rock (3/8") evenly for consistent coverage. When using near fire pits, keep a safe distance from flammable materials and ensure good ventilation. These steps help maintain both the appearance and function of the product over time.

Technical Specifications Table

Pricing and Delivery Examples

Black Lava Rock (3/8") is available for delivery across the United States. Pricing varies by location, reflecting local sourcing and delivery costs. The following table shows sample prices per ton for selected cities, along with their delivery charges. All prices include delivery and applicable taxes. Enter your ZIP code on the Gravelshop website to see exact pricing for your area.

Delivery is included in the price shown when you enter your ZIP code on our website. You can select your preferred delivery date and time during checkout. For deliveries, the road must be at least 12 feet wide and suitable for heavy trucks. If you are not present at the time of delivery, the material will be left at the most suitable spot as determined by the driver, and you are responsible for unattended deliveries.

Ordering and Service Information from Gravelshop

You can order Black Lava Rock (3/8") online in less than a minute. All prices include sales tax and delivery-there are no hidden fees. Payment can be made using major credit cards or mobile payment options. After placing your order, you will receive a confirmation email with your order and delivery details. If you have special delivery instructions, you can enter them at checkout or mark the delivery location outside your property.

Gravelshop operates in 31 U.S. states and partners with verified local suppliers to provide fast, reliable deliveries. If you need help choosing the right amount, use our material calculator on the product page. We do not offer spreading or landscaping services; delivery is for material only. For questions or larger orders, contact our support team by phone or email.

Summary

Black Lava Rock (3/8") is a decorative, porous, and lightweight volcanic stone suited for landscaping, fire pits, walkways, and drainage applications. It is not intended for structural use, playgrounds, or high-traffic driveways. The rock is delivered in bulk or bags, with pricing and delivery included. For accurate pricing, enter your ZIP code on our website. Gravelshop provides easy online ordering and reliable delivery to meet your project needs.