Using different types of gravel to line walkways, driveways, gardens, and other outdoor areas is a nice and efficient way to decorate or enhance a space without signing yourself up to the high amount of maintenance that other types of ground coverings, like grass, can sometimes require. Gravel can largely be divided into two categories, including man-made and naturally harvested. Each of these categories has a variety of types and are best suited for different purposes.
The term man-made can be a bit misleading, as a lot of this type of gravel consists of naturally-occurring stone. This term refers more to the processing of gravel than the material itself. As gravel that is considered man-made is actually mechanically crushed and sometimes repeatedly filtered through various sizes of mesh. This type of gravel is usually better suited for driveways and walkways, generally any areas which have contact with larger and heavier objects.
The most common type of man-made gravel is granite, which tends to be grayish with white swirls or specks. The larger cuts are great for driveways, borders, and for drainage purposes, while finer cuts can be used as pavement for stone beds or decoration in gardens. Most granite gravel is priced affordably and easy to get.
Crimson stone is reddish-purple in color, it catches the eye well and adds a bit of originality to your space. Usually about a half to one inch in diameter, these can be well utilized in lawn pathways for contrast. The larger the stone, however, the less bold the color you'll get with this type.
Slate gravel is smaller, dark gray in color, and good for drainage purposes. Lag gravel describes the more coarse type of gravel that is accumulated after finer particles have specifically filtered out.
Though it sounds like an umbrella term, crushed stone gravel specifically refers to limestone or dolemite that has been crushed and filtered into different sizes. Sizes can range from 1/4 to 3/8 of an inch in diameter, and often are sharply-edged. This type of gravel is most typically used in the production of concrete, as it is used as a compacted base with tar in surfaces for roads and driveways.
Naturally harvested gravel is gravel that has been harvested and shaped by natural sources, usually rivers, which typically produces gravel that is smooth, round or oval. The reason for their smooth texture is due to years of water erosion, making them more ideal for borders and gardens.
Pea gravel is one of the most popular types of naturally harvested gravel, and is characterized by its small round shape and sandy color. Depending on the size of your pea gravel, you can use it for walkways or even in home aquariums and small ponds. There is also a variety in color as well. Though pea gravel is typically beige or off-white, it is possible to order special blends that have a range of tones to create an overall effect. For example, mixing together pea gravel that is blue, gray, and white can create a more oceanic theme. If you like the look of pea gravel but want to use it for areas with more heavy-duty purposes, you can combine it with concrete to reap the best of both worlds. One drawback of this type of gravel, however, is that it can become easily stuck on the bottoms of shoes with divots, and can tend to escape their edging barriers easily because their texture is so smooth. That's why it's a good idea to use these in concurrence with larger flat stepping stones, bricks, plastic metal, or pressure-treated wood that can act to reign in on any disorder and make walking through the gravel a lot less of a hassle.
Bank gravel is any sort of naturally harvested gravel mixed with sand or clay. Lava rock is one of the more sharply edged types of gravel, typified by a reddish-brown color, and a light weight. Quartzite is brighter and whiter, but similar in texture to pea gravel. Pay dirt gravel, is extracted via panning for gold, and has a high concentration of precious metals as well as gold. Piedmont gravel describes gravel that is found on slow-water flowing flat grounds, but originates from mountain streams. Bench gravel, although originated from a stream, has maintained its position on the side of a valley after that stream has reached a lower water level. And lastly, plateau gravel is similar to bench gravel, except that it is found on a plateau instead of a valley.