Neighborhood Rocks: Names for All Our Rocks

	On this page we show you photos of all the types of rocks that we find in the yards, gardens, streets, parking lots, and railroad tracks near our home. We also include examples of "fake rocks" made by people, like concrete and slag. Once you know a rock's name, you can learn more by clicking on its picture or name.

White Marble

	Mostly bright white.
	Made of medium-sized crystals that glitter in sunlight.
	You can scratch it with a nail or knife, and the rock bubbles in vinegar or acid.

White Chert

	Mostly white, sometimes chalky looking or smooth.
	Broken edges may be sharp or scalloped.
	Nail doesn't scratch it and it does not bubble in vinegar.

White Granite

	Mostly white or yellowish, with dark specks.
	Small broken crystal surfaces shine in sunlight.
	Nail doesn't scratch it and it does not bubble in vinegar.

Dolostone

	Mostly light gray.
	You can scratch it with a nail or knife.
	Only powdered rock bubbles in vinegar or acid.

Limestone

	Light to dark gray.
	You can scratch it with a nail or knife.
	Rock bubbles in vinegar or acid.

Gray Slag

	Light to dark gray or yellowish.
	Dull to somewhat glassy.
	Usually has lots of rounded bubble holes.
	Some spots bubble in vinegar or acid, but most place do not.

Quartz (from Pegmatite)

	Cloudy white, a bit pinkish, or clear.
	Looks a bit like broken glass.
	Nail doesn't scratch it and it does not bubble in vinegar or acid.

Quartzite pebbles

	White (also yellowish or light brown).
	Can see large sand grains -- sometimes crumbly.
	Nail doesn't scratch it and it does not bubble in vinegar or acid.

Slate

	Dark gray, looks silky in the sun.
	Breaks into mostly flat pieces.

Basalt or "Trap Rock"

	Dark gray, dull looking.
	Mostly fine-grained, but may contain scattered larger crystals.
	Breaks into chunks with smooth sides.

Scoria (type of Basalt)

	Black or reddish.
	Lots of rounded bubble holes.
	Doesn't float in water.

Slag (human-made lava)

	Black, whitish, or reddish.
	Some rounded bubble holes, but mixed with crumbly places and smooth glassy spots.
	Some parts fizz in acid.

Obsidian or Volcanic Glass

	Draws no line or a white line on the sidewalk.
	Hard to break -- if you do break it, sharp edges can cut you!

Coal

	Draws a black line if you scrape it on the sidewalk.
	Pretty easy to break into a mix of blocky, crumbly, and powdery pieces that leave your hands dirty!

Gabbro

	Looks dark gray, but really a mix of black and light crystals.
	Small broken crystal surfaces shine in sunlight.

Scoria (a type of Basalt)

	Reddish or black.
	Lots of bubble holes.
	Doesn't float in water.

Pink Quartzite

	Pink, sometimes yellowish.
	If you look closely, you may see some pieces are made of sand-sized grains.

Red Granite

	Mostly reddish pink, but...
	...if you look closely, you'll also see gray and purplish spots.

Saprolite ("weathered" granite)

	Most pieces stained rusty red or coated with a dark reddish crust.
	If you look closely, you'll see pink, gray, and darker crystals (like in Red Granite).

Pegmatite (like granite, but with really big crystals!)

	Pink pieces mixed with whitish, gray, and silvery pieces.
	Most pieces are made of only a few large crystals.

Quartz rock

	Most pieces stained rusty red or yellowish, or coated with rusty-red powder.
	If you look closely, you'll see small, pointy crystals and thinly layered rock.

Brown Chert

	Mostly brown, but mixed with cream and darker colors.
	Some sides look really smooth, but freshly broken edges may be sharp!
	Nail doesn't scratch it (but may leave a dark line).

Pumice

	Tan or gray.
	Lots of bubble holes.
	Feels very light in weight, for a rock.
	Dry pieces often float in water.

Quartzite pebbles

	Brownish, yellowish, or white.
	Can see large sand grains in some pieces -- sometimes crumbly.
	Nail doesn't scratch it (but may leave a dark line).

Brown Quartzite pebbles

	Brownish, tan, white, or reddish.
	Outside very rounded and smooth.
	Broken edges look glassy and may be sharp.
	Nail doesn't scratch it (but may leave a dark line).

	White or light gray
	Dark gray or black
	Red or pink or rusty looking
	Brown, tan, or yellowish
	Silvery

Neighborhood Rocks Search this Site

Names for All Our Rocks

White or light gray

Dark gray or black

Red or pink or rusty looking

Brown, tan, or yellowish

Silvery

If you didn't find your rock yet:

	Rounded pebbles If you have a rounded pebble from a beach or river gravel, you may have to go to this page to find its name.