Gravel is a composition of loose rock fragments naturally occurring or industrially produced by crushing hard-wearing rocks such as limestone, sandstone, or basalt in quarries called gravel pits.

Natural Stone Gravel

These rocks form naturally without human intervention. They are found on river channels or river floodplains due to erosion through water action or weathering of rocks.  Examples include bank, bench, lag, pea, piedmont, and plateau gravel. They come in different sizes and colors and are composed of quartz grains.

Crushed Stone Gravel

This is gravel formed due to human intervention such as mining. They include crushed stone and stone dust which are a result of machine crushing.

Physical Difference

Whereas the stones are similar in their chemical composition, they look different physically.  The significantly noticeable difference between the natural and crushed gravel stones is the surfaces. 

The natural ones have smooth, rounded surfaces, while the crushed ones tend to have rough, jagged edges.

Uses

Many people use crushed gravel mixed with natural stone on driveways or landscaping for aesthetic purposes. Depending on the purpose for which they are intended or the desired look, stone gravel suppliers mix different stones at different ratios to achieve your desired result.

Gravel mixed with sand is used to make building materials such as blocks, pipes, and bricks. It is similarly used as an ingredient in making concrete used in building and road construction. Additionally, it is also mixed with asphalt and used in road construction or used as a base layer on which tarmac is layered.

The gravel pebbles' angularity, hardness, and size properties make it a highly effective water filtration medium.  For this purpose, the physical specifications of size should be small enough to hold back impurities contained in sediments.

In areas susceptible to poor drainage and erosion, control can be done using fist-sized gravel. This prevents surface water runoff from carrying away the soil. In addition, you can place pebbles below the roof in the absence of a gutter to keep roof water from splashing soil and dirtying the walls.

Of Note

More often than not, the size of the gravel stone is to be put into the highest consideration for different usage. 

Different sizes will work optimally for different purposes. For example, the size that works best on a walkway is not necessarily one that works in a filtration system or a rock garden. A user should always check with their stone gravel supplier for advice on what works best and where before procuring the material.

Talk to a stone gravel supplier to order your gravel.