Both gravel and limestone are great alternatives to typical paved walkways or driveways. They are similar in that both of the materials are easily replaceable, have a fair amount of variety and options in their aethetic values, and are more environmentally friendly than paved areas because they let groundwater through and help prevent erosion. However, it is important to recognize the distinct differences between the two materials when selecting them for use.
Limestone is a very specific type of rock, and limestone used as a medium for walkways or driveways is hewn from the many places limestone deposits are found. This sedimentary rock compound is not hard to find, existing virtually everywhere that was ever beneath a sea.
Gravel is also found near past or present water sources; however, it does not consist of one rock but, rather, is defined as smooth water-worn rocks. The term "gravel" is a very broad one and can sometimes be applied to limestone itself.
Limestone does not vary much in color. It is always a variant of gray, sometimes a very dark, deep slate gray and at other times very light and almost off-white in color.
Gravel can vary immensely in color. Usually, gravel purchased in bulk comes as a standard mixture of stones in varying shades of brown, gray and white. However, special mixtures of specific colors or combinations of color can be found as well, giving the homeowner a lot of freedom to match his driveway or walking path to the surrounding landscape and house.
Quarried limestone is very jagged and nonuniform. The shape of an individual stone is usually sharp and asymmetrical. Limestone is readily available in many sizes, from limestone crushed almost into a powder to large 6-foot boulders, and all sizes in between. Typically, smaller sizes are smoother than larger sizes.
Gravel is usually very smooth and round- or oval-shaped, having been shaped over the years naturally in streams or riverbeds. Gravel also varies hugely in size, from rocks the size of fists down to tiny pebbles the size of peas and smaller.
Limestone is commonly used for nature trails and large driveways or property roads, where aesthetics are not a primary necessity, but forming a long-lasting and effective path is important.
Gravel is more commonly used for driveways with high visibility and for other landscaping beautification projects. Larger stone of either type is often used as a base for a top layer of smaller stone, as it lasts longer but creates coarse and impractical surfaces for walking or driving on.