Gritting Salt vs Rock Salt – Are They the Same?
With winter and potential snowfall just around the corner, the de-icing essential, also known as gritting salt, often becomes the new ‘hot topic’. Since different people and publications call it different things it can be very confusing to understand what gritting salt actually is. Is it the same as rock salt, de-icing salt, road salt, or even snow salt?
Whether you are looking to buy gritting salt or simply want to learn more about it, this blog will provide you with all the answers you need.
What is gritting salt?
Gritting salt, also commonly known as grit salt, snow salt, road salt, or its proper name – rock salt - is widely used for winter de-icing. While there are two types of rock salt used for de-icing – white and brown – gritting salt typically refers to the brown variety.
It works by lowering the freezing point of water, preventing ice from forming or helping to melt ice that has already developed, making it a winter de-icing essential.
Highway agencies often use gritters to spread it across various types of roads, including motorways, major roads, and residential streets, to ensure they remain safe for drivers. Interestingly responsibility for de-icing major trunk roads falls to the National Highways Agency and all others to individual local councils which is why snow clearance varies area to area. Additionally, individuals and businesses often use it on pavements, car parks, and driveways.
Where does rock salt come from?
Rock salt forms when salty bodies of water evaporate, typically around dry lakebeds, inland seas, and estuaries in arid regions.
In ancient times, large water bodies, including the Mediterranean Sea, evaporated leaving behind massive salt deposits.
Overtime, these deposits were buried by sediments, but the less-dense salt often pushed upward, forming dome-like structures now buried beneath additional layers.
Today, these deposits are accessed through mining processes such as drilling and excavation in salt mines. Check out our What is Rock Salt blog to learn more about this process.
The depth of salt mines can vary significantly; for example, the world’s largest operating salt mine is located over 500 metres beneath Lake Huron in Goderich, Ontario.
In comparison, Winsford Mine, Britain’s largest operational salt mine and Online Rock Salt’s supplier, is located nearly 200 metres underground. Operating since 1844, it is also the oldest working salt mine in the UK.
Many salt mines worldwide are open to visitors, including Poland's Wieliczka Salt Mine. Famous for its elaborate tunnels and chambers carved entirely from salt, it attracts over 1.5 million visitors annually. This remarkable site extends to a depth of 327 metres and even features an underground lake filled with natural brine!
Brown Rock Salt vs White Rock Salt
Brown rock salt or gritting salt is the most used variety of de-icing salt. It gets its distinctive brown colour from the natural clay content found in the salt beds, which gives it a ‘gritty’ texture. The presence of clay in the salt means it’s more abrasive, which helps improve traction on slippery surfaces—an essential quality for preventing accidents during icy conditions! Brown rock salt is often more affordable compared to white rock salt, making it a practical option for large areas like roads, parking lots, and industrial sites.
However, while effective for de-icing, it can leave behind a slightly brown residue that stains surfaces and can be difficult to clean, particularly on decorative stone, or vehicles. This is why it is mainly used in locations where this is not a concern.
The white variant of rock salt contains less clay, which is why it does not have the brown colour. However, most of ‘white rock salt’ in UK refers to marine salt, also called white de-icing salt, which is created by evaporating fresh sea water, leaving the natural white salt behind. This ancient method of extracting white salt dates back over 8,000 years, with archaeological evidence showing saltworks in both Romania and China. It also requires climates that are warmer than what UK has to offer, so here at Online Rock Salt we source our products from warmer, Mediterranean locations. Check out our White Salt Production blog to find out more.
This option is more aesthetically pleasing than the brown variant as it doesn’t leave behind the gritty residue or stains that can discolour pavements or vehicles. Due to this, many businesses, including schools or retail outlets where people constantly go in and out of the building, prefer this option. However, it is typically more expensive than rock salt, so may be a slightly more costly solution if de-icing a large area.
Although it seems confusing at first, all the different names for gritting salt refer to the same thing – brown rock salt. It can be locally mined here in the UK and is very effective in de-icing, while also being a great budget option. However, it does leave a slight brown residue behind due to its clay content.
White rock salt which has less clay also exists, but it’s not popular here in the UK. Most companies promoting white rock salt are selling white marine salt (white de-icing salt), which is a pricier but ‘cleaner’ version due to the lack of residue.
If you would like to learn more about different types of de-icing salt, feel free to visit our Knowledge Base for more blogs like this one.
