Garnet
Garnet is a naturally occurring mineral that's become the industry standard for general-purpose abrasive blasting. With a hardness of 6.5 to 7.5 on the Mohs scale, it cuts efficiently through rust, paint, and mill scale while producing a clean, angular surface profile that coatings bond to extremely well.
Best for: General-purpose mobile blasting, rust removal from structural steel, paint stripping, concrete profiling, equipment cleaning. It's the workhorse media for most of the work we do across Gainesville, Buford, and the rest of northeast Georgia.
Mohs hardness: 6.5–7.5. Profile produced: Angular, CSP-3 to CSP-5 on concrete. Dust level: Low to moderate. Recyclability: 2–5 cycles in contained systems, single-use in portable operations. Cost: Mid-range, approximately $0.30–$0.50 per pound in bulk. Health hazard: No free silica — safe with standard PPE.
Aluminum Oxide
Aluminum oxide is the second-hardest common abrasive at 9 on the Mohs scale — just below diamond. It's the most aggressive cutting media available and the go-to choice for industrial applications where speed and deep profiling matter more than media cost.
Best for: Heavy industrial surface prep, deep rust removal, thick coating removal, manufacturing equipment restoration, structural steel blasted to SSPC-SP10 (near-white) standard. Any project where you need maximum material removal in minimum time.
Mohs hardness: 9. Profile produced: Deep angular, aggressive. Dust level: Low. Recyclability: 5–10+ cycles — the most recyclable common media. Cost: Higher upfront ($0.50–$1.00/lb) but offset by recyclability. Health hazard: No free silica — safe with standard PPE.
Caution: Because aluminum oxide is so aggressive, it can damage softer substrates. Don't use it on wood, soft metals, thin sheet metal, or any surface where you need to preserve the existing profile. On thin steel, excessive pressure with aluminum oxide can warp the material from frictional heat.
Glass Bead
Glass bead is a spherical media — round instead of angular. This means it peens the surface (compresses and smooths) rather than cutting into it. The result is a smooth, satin-like finish rather than the rough anchor profile that angular media create.
Best for: Finishing work, cleaning stainless steel, brightening aluminum, peening (inducing compressive stress for fatigue resistance), automotive component cleaning, and any application where a smooth finish is desired rather than a rough profile.
Mohs hardness: 5.5–6. Profile produced: Smooth, peened — not suitable for coating adhesion profiles. Dust level: Low. Recyclability: 20–30 cycles at proper pressure. Cost: $1.50–$2.50 per pound. Health hazard: No free silica.
Important: Glass bead does not create the angular profile most protective coatings require. If you're blasting to prepare a surface for primer and paint, glass bead is usually the wrong choice. It's a finishing and cleaning media, not a profiling media.
Crushed Glass
Crushed glass — made from recycled bottles and windows — has become one of the most popular mobile blasting media in recent years. It performs similarly to sand (angular particles, good cutting ability) without the silicosis hazard of silica sand. It's also environmentally friendly since it's 100% recycled material.
Best for: Mobile and portable blasting, general surface prep, rust and paint removal, concrete profiling. Popular with dustless/wet blasting operations. Excellent for construction equipment cleaning and farm equipment restoration where the media is used once and disposed.
Mohs hardness: 5.5–6. Profile produced: Angular, comparable to sand. Dust level: Low (especially in wet blasting). Recyclability: Single-use in portable operations due to fragmentation. Cost: Low, approximately $0.10–$0.25 per pound — one of the cheapest media available. Health hazard: No free silica.
Soda (Sodium Bicarbonate)
Soda blasting uses industrial-grade sodium bicarbonate (baking soda) as the abrasive. It's the gentlest commonly used blasting media — soft enough to remove coatings from brick, wood, and decorative metalwork without altering the substrate underneath.
Best for: Historic building restoration, wood cleaning and stripping, delicate metalwork cleaning, graffiti removal, automotive interior cleaning, food processing equipment (FDA-approved, water-soluble). Ideal for projects where preserving the original surface is critical — like the historic downtown buildings in Dahlonega or Athens.
Mohs hardness: 2.5. Profile produced: Minimal to none — cleans without profiling. Dust level: Moderate (fine particles). Recyclability: Not recyclable — dissolves in water. Cost: $0.50–$1.00 per pound. Health hazard: Non-toxic, though respiratory protection is still required for any airborne particulate.
Important: Soda does not create a surface profile. If the next step is applying a coating that requires mechanical adhesion (like epoxy or primer), soda blasting alone won't provide the necessary anchor pattern. It's a cleaning and stripping media, not a profiling media. A second pass with a harder media may be needed if coating adhesion is the goal.
Walnut Shell
Walnut shell is a soft, organic blasting media made from crushed walnut shells. It removes coatings without scratching or profiling the underlying surface, making it suitable for aerospace, automotive, and delicate restoration applications.
Best for: Stripping paint from soft metals, fiberglass, and wood without surface damage. Automotive restoration of aluminum and fiberglass components. Cleaning engine parts, mold cleaning, and deburring soft materials.
Mohs hardness: 3–4. Profile produced: Minimal — cleans without significant profiling. Dust level: Moderate. Recyclability: Limited, 2–3 cycles. Cost: $1–$2 per pound. Health hazard: Non-toxic, but can harbor mold in humid environments — a real consideration in Georgia's climate. Not recommended for use in enclosed blast cabinets for this reason.
Steel Grit and Steel Shot
Steel grit (angular) and steel shot (spherical) are the heaviest and most aggressive metallic blasting media. They're primarily used in industrial blast rooms, shipyards, and bridge maintenance operations — environments where the media is recycled through mechanical recovery systems.
Best for: Large-scale industrial surface prep in contained facilities, shipyard hull blasting, bridge and infrastructure maintenance, heavy mill scale removal, shot peening for fatigue resistance.
Mohs hardness: 7–8 (grit), 6–7 (shot). Profile produced: Very aggressive (grit) or smooth peened (shot). Recyclability: Highly recyclable — hundreds of cycles in contained systems. Cost: High upfront ($0.80–$1.50/lb) but very economical per cycle. Health hazard: No free silica, but heavy metal contamination possible with recycled steel. Not practical for mobile operations due to weight and recovery requirements.
Plastic Media
Plastic abrasive comes in various hardness grades (Type I through Type V) and is used primarily for coating removal from substrates that can't tolerate harder media. It strips coatings without cutting into the base material.
Best for: Stripping coatings from composite materials, fiberglass, aluminum aircraft components, and any surface where you need to remove a coating without touching the base material. Common in aerospace and automotive restoration.
Mohs hardness: 3–4 (varies by type). Profile produced: Minimal to none. Recyclability: Multiple cycles in contained systems. Cost: $2–$5 per pound — one of the more expensive media. Health hazard: Non-toxic.
Silica Sand — Why It's No Longer Used
Silica sand was the original blasting media (hence "sandblasting"), and it's cheap and effective. However, it contains crystalline silica that causes silicosis when inhaled — a progressive, irreversible, potentially fatal lung disease. OSHA classifies respirable crystalline silica as a known carcinogen. Multiple European countries banned silica sandblasting as early as 1947.
Every alternative media listed above performs as well or better than silica sand without the health risk. There is no good reason to use silica sand for blasting in 2026. Any company still using it is either uninformed or cutting corners at the expense of worker safety. For a deeper dive on this topic, see our post on sandblasting vs. abrasive blasting.
How to Choose the Right Media for Your Project
Start with three questions:
1. What surface are you blasting? Hard surfaces (structural steel, concrete) can handle aggressive media like garnet or aluminum oxide. Soft or delicate surfaces (brick, wood, thin metal, historic materials) need gentle media like soda, walnut shell, or glass bead at reduced pressure.
2. What are you removing? Heavy rust and industrial coatings need aggressive cutting media. Light paint and surface contamination can be handled with softer options. Multiple layers of old coating over corrosion typically need a harder media and multiple passes.
3. What comes next? If a protective coating is being applied, check the manufacturer's spec for required CSP. Angular media (garnet, aluminum oxide, crushed glass) create profiles for coating adhesion. Spherical media (glass bead) and soft media (soda, walnut) don't. If nothing is being applied — you're just cleaning — then the profile requirement doesn't apply.
When you contact Strickland Surface Preparation, we evaluate all three factors and select the media that produces the best result for your specific project. We don't default to one media for everything — we match the media to the surface, the removal requirement, and the coating specification.
Frequently Asked Questions
What is the best all-around blasting media?
Garnet. It offers the best balance of cutting speed, surface profile consistency, low dust, and cost for most general-purpose work on steel and concrete.
What media is safest for historic buildings?
Soda and walnut shell remove coatings without altering the substrate. Glass bead at low pressure works for delicate metalwork. All three preserve original surfaces.
Can I reuse blasting media?
Depends on the type. Aluminum oxide gets 5-10+ recycles. Glass bead gets 20-30. Garnet gets 2-5. Crushed glass, soda, and walnut shell are typically single-use in portable operations.
What media works best for concrete floors?
Garnet or crushed glass at moderate pressure produces the CSP-3 to CSP-5 profiles most floor coatings require. Avoid steel grit on concrete — it can leave metallic contamination that causes rust staining.
Is silica sand still used?
Rarely and it shouldn't be. It causes silicosis — a serious, irreversible lung disease. Every modern alternative performs as well or better without the health risk.