Washed gravel has the appearance of river rock, which means it is often more affordable than actual river rock. The individual rocks are about 1 to 2 inches in diameter.

Washed gravel: Cleaned of all dirt and dust, this landscaping rock looks like smooth river rocks.

It's lightweight to transport and popular for landscaping, planters, gas grills, and roofing granules. Freeze-thaw cycles and heavy weight can make these rocks break down over time.

Volcanic scoria: This volcanic rock was formed with voids where gas bubbles were trapped as the rock solidified.

It can range in size from small pieces of rocky grain to 1.5 inches in diameter, and the color varies from black and gray to hues of red, blue, and purple.

Slate: This fine, clay metamorphic rock is commonly used for sidewalk slabs, roofs, flooring, countertops, and chalkboards.

This option is not popular for long-term use in areas with freeze-thaw cycles which can break apart the stone. Water can seep into the spaces in this material making it porous.

Sandstone: Made by sand cemented together by calcite, clay, or silicate minerals.

It is used for erosion control or slope stabilization.

Riprap: Layer of larger stone, cobbles, or boulders it can be a variety of rocky material, ranging from 4-inches to 2 feet in size.

Iron and steel slag are the byproduct rocks that result from smelting ores.

Recycled stone substitutes: Crushed stone substitutes include sand and gravel, splintered or expanded clay or shale, perlite, vermiculite, and slag.

It is also used for road construction, rubble, and in between railroad tracks. Quartzite: Quartzite is sandstone that has gone through metamorphisis it has heated and compressed, welding into a durable rock that can be difficult to mine, handle, and transport.Limestone is easily crushed and used in cement, ready-mix concrete, and is the foundation construction material for roads, buildings, and railroads. Limestone: Made of calcium carbonate, it is the most popular crushed stone option.It is commonly used as construction aggregate. It's basically a coarse sand that may contain small pebbles. Grit or gritstone: This is a hard, coarse-grained sandstone.The igneous rocks in this group are called granite, granodiorite, diorite, and rhyolite. It is a household favorite, chosen for its color and durability. Granite: Granite refers to any light-colored igneous rock that is used in construction.It is the most abundant rock in the deep oceanic crust and is commonly used as the crushed stone base at construction sites, countertops, floor tiles, and pavers. It is usually black or dark green, made of plagioclase and augite minerals. Gabbro: Sometimes called 'black granite,' gabbro is a coarse-grained, dark-colored igneous rock.It is commonly crushed for use in construction projects, including roads, concrete, and asphalt. It is typically a dense dark rock colored blue, grey-blue, dark-grey, or black with a fine-grained texture.

Basalt: Basalt is an igneous rock that formed from molten rock material (lava or magma).It can resist heat, impacts, water, scratches, staining, wind, and acid, and is commonly used as a component in cement and mortar. It has fine grains and a rough, dull texture that can be polished to shine. It's stronger than shale and doesn't cleave like slate. Argillite: This dark blue rock has flecks of green and red and is a durable, highly compact sedimentary or metamorphic rock made of clay or silt.

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Crush and run gravel