Gilsonite Sealer: What It Is, How It Compares, and When It Makes Sense

Gilsonite sealer is a driveway and pavement sealer made from gilsonite, a hard, natural form of asphalt mined mainly in Utah's Uinta Basin, dissolved in a petroleum solvent. Unlike thick, water-based emulsion sealcoats that form a film on top, gilsonite sealers are thin and designed to soak into the asphalt surface, darkening it to a deep black and replenishing some of the binder lost to weathering. They typically dry fast and can look excellent on newer, smooth driveways. The trade-offs are solvent fumes, higher VOC content that's restricted in some areas, flammability during application, and less ability to fill surface texture than a sand-filled emulsion.

Driveway sealer calculator →

What Is Gilsonite?

Gilsonite, also called uintaite or asphaltite, is a natural, glossy black hydrocarbon resin found in vertical veins in northeastern Utah. It's harder and more brittle than refined asphalt binder, with a high softening point, and it dissolves readily in certain solvents. It's used in more than sealers: oil well drilling fluids, printing inks, paints, foundry sands and as an asphalt modifier. "Gilsonite" is also a trademark associated with one producer, so you'll see generic terms like natural asphalt or uintaite as well. It belongs to the same family of natural asphalts as lake asphalt; our article on asphalt lakes covers another natural source.

How Gilsonite Sealers Work

• Penetration: the solvent carries dissolved gilsonite into the pores of the asphalt surface.
• Evaporation: the solvent flashes off, leaving the natural asphalt resin bonded in the top layer.
• Color: the result is a rich, dark black that many homeowners like.
• Thin coat: coverage is typically much higher per gallon than thick emulsions, because it's a thin, penetrating product rather than a filled coating.

Some manufacturers also make water-based or emulsified gilsonite products that lower VOCs, so check the label to see which kind you're buying.

Gilsonite vs Asphalt Emulsion vs Coal Tar

Sealer type	Base	Strengths	Weaknesses
Gilsonite (solvent-based)	Natural asphalt in petroleum solvent	Penetrates, deep black color, fast drying	Fumes, high VOCs, flammable, little filling of rough texture
Asphalt emulsion	Refined asphalt in water with fillers	Low odor, lower VOCs, can include sand for texture	Slower drying, film can wear or peel if overapplied
Refined coal tar	Coal tar pitch emulsion	Fuel and chemical resistance	High PAH content; banned or restricted in some places
Acrylic/polymer	Synthetic resins	Durable, color options	Usually higher cost

Our comparison of oil-based vs water-based driveway sealer covers the broader choice, including compatibility between product types.

Pros of Gilsonite Sealer

• Deep black finish that restores a fresh look to faded asphalt.
• Fast drying in many conditions, sometimes allowing traffic sooner than emulsions.
• Penetrates rather than coating, so less risk of thick film peeling.
• Wider application window: solvent-based products may tolerate cooler temperatures than water-based ones; check the label.

Cons and Cautions

• Strong solvent fumes: apply outdoors with ventilation, away from open windows, pets and kids.
• Flammability: no smoking, sparks or open flames nearby; store and dispose of rags properly.
• VOC restrictions: some states and air districts limit VOCs in sealers, which can restrict or ban certain solvent-based products. Check what's legal where you live.
• Doesn't fill texture: it won't smooth rough, porous or open-textured surfaces the way a sand-filled emulsion does.
• Slipperiness: glossy, thin coats can be slick when wet, especially without added grit.
• Overapplication: too much solvent can soften the asphalt surface; follow coverage rates.
• Health warnings: read the safety data sheet; many solvent products carry health and handling cautions.

When Gilsonite Makes Sense

• Newer or smooth driveways that need color and protection but not texture filling.
• Cooler-season applications where a water-based sealer won't cure well, if the label allows it.
• Contractors who want quick turnaround on driveways and have proper spray equipment and safety practices.

It's less suitable for rough, heavily weathered surfaces with lots of exposed stone, for areas with strict VOC rules, or for homeowners sensitive to odors. On older driveways, crack filling and a filled emulsion often do more good.

How to Apply

1. Check the weather and label. Follow the product's temperature and rain-free window.
2. Clean and dry the surface. Sweep, blow and remove oil spots; primer may be needed on oil stains.
3. Fill cracks first with a compatible asphalt crack filler and let it cure.
4. Apply thinly and evenly with a sprayer, squeegee or brush, as the maker recommends. Avoid puddles.
5. Keep traffic off until it's dry per the label, then allow extra time before heavy vehicles or turning tires.

Wear chemical-resistant gloves and consider an organic vapor respirator if the label recommends respiratory protection. For step-by-step basics that apply to most sealers, see our how to sealcoat an asphalt driveway guide.

How Much Do You Need?

Coverage for thin penetrating sealers is usually listed on the container in square feet per gallon and is typically higher than for thick emulsions. Porous or weathered surfaces absorb more. Measure the driveway area, divide by the label coverage, and add a margin. The driveway sealer calculator linked above estimates gallons from area and coverage rate.

Gilsonite Beyond Sealers

You may also run into gilsonite in paving specs. Small amounts are sometimes blended into hot mix or binder as a modifier to stiffen it and improve rutting resistance in hot climates or under heavy traffic. That's a plant-level decision made by engineers and suppliers, not something homeowners choose. It's a reminder that gilsonite is simply a very hard natural asphalt: the same material that stiffens a highway mix can, when dissolved thin in solvent, soak into a driveway surface and darken it. The two uses have little in common beyond the raw material.

Bottom Line on Gilsonite Sealer

Gilsonite sealer is a solvent-based, natural-asphalt product that soaks in and turns asphalt deep black, dries quickly and suits smoother, newer driveways. It doesn't fill rough texture, gives off strong fumes and may be restricted by VOC rules. Check local regulations, follow the label closely, and choose a filled emulsion if your driveway needs texture repair more than color.