Walnut Shell is an organic abrasive commonly used to polish and clean soft metals, fiberglass, wood, and stone. Specific applications include fire & smoke remediation, graffiti removal, brick restoration, automotive restoration and specialty petrochemical or offshore applications where a minimal sparking, non-ferrous abrasive is required. Walnut Shell will clean metal parts without etching or pitting the surface. Walnut Shell does not contain heavy metals or free silica. Walnut Shell is resistant to rupture and deformation, allowing for it to be recycled up to four times.


Walnut Shell is typically blasted at 60–90 PSI to achieve the most productive results. This lower PSI, along with walnut shell’s durability, produces lower dust levels than most mineral or slag abrasives. Low dust levels improve the operator’s visibility of the work surface, increasing production rates. Lower dust levels also reduce cleanup costs on the work site.


Walnut Shell is a biodegradable and non-toxic abrasive produced from crushed walnut shells. It is low-dusting, can be easily disposed of, and it is non-hazardous. Walnut Shell is a minimal sparking, non-ferrous abrasive that does not contain any heavy metals or free silica.


Walnut Shell is a biodegradable and non-toxic abrasive that can easily perform a wide variety of abrasive abrasive blasting jobs. Coarse sizes can be used for stripping auto and truck panels, and cleaning delicate molds. Medium sizes are suited for cleaning moldings, castings and electrical parts. Fine sizes work best for light duty work and allow for fine detail work.

Walnut Shells


Shape: Angular
Hardness: 3.0 Mohs
Bulk Density: 32–43 lbs./cu. ft.
Specific Gravity: 1.35 g/cc
Free Silica: No Free Silica
Organic Abrasive


Recommended nozzle pressure: 60–90 psi
Recommended working distance from surface: 6–36 inches


Bulk Bags: 2,000 lbs.
Bags: 50 lbs.


812 (Coarse) – Minimal to no mil profile produced
1220 (Medium) – Minimal to no mil profile produced
2030 (Fine) – Minimal to no mil profile produced
30100 (Extra-Fine) – Minimal to no mil profile produced

Optional Accessories

Blast Hose

Blastmaster® Abrasive Blasting Hose

Blastmaster® Abrasive Blasting Hose is available in standard lengths of 50, 100 and 400 feet, and custom lengths up to 200 feet.

Blast Nozzles

Abrasive Blasting Nozzles

A wide variety of blast nozzles are available to meet even the most challenging work site requirements.

Blastmaster® Abrasive Metering Valves

Blastmaster® Abrasive Metering Valves

Marco’s wide selection of Blastmaster® Abrasive Metering Valves give you variable and instant abrasive control for great results on every work site.

Couplings and Blast Nozzle Holders

Couplings and Nozzle Holders

Marco offers several types of couplings and blast nozzle holders to meet the needs of a wide variety of applications.


Technical Information


Inhaling dusts from abrasive blasting may result in serious injury, disease, or death.
According to OSHA, only a Type CE NIOSH-certified blasting airline respirator with positive pressure blasting helmet should be used for abrasive blasting.

Product details are based on published information at the time of publication. Product details are subject to change without notice. Contact Marco for more information.