There are very few landscape projects that don’t require sand. It’s a critical component in every concrete and mortar mix, it’s ideal for creating a level surface on which to lay pavers, and to sweep between the joints when you’re finished. Sand is perfect as a drainage material, and it’s great for the kids to play in, too.
But you should decide what type you need as the different forms have different uses. Select the right one and your job will be a whole lot easier, not to mention more professional. So read on to find out all you need to know about the most common sands you’ll encounter.
What is sand?
Sand is one of the materials left by the erosion of various forms of rocks. To be described as sand the individual grains must be between 0.06mm and 2mm. If the grains are smaller the material is silt, larger and it is gravel. The colour of sand is determined by both its parent material and any additional materials, such as silt or minerals, that may be present.
This is the fine stuff we all think of when we think of sand. When dry it will run through your fingers. A washed sand is beach or sharp sand that has been cleaned of impurities, such as salt. Sharp refers to the grains – they are angular, which is a sign of ‘new’, recently created sand, not ‘old’ sand that has tumbled down a river. Fine river sand may also be sold as washed sand. Sharp sand is less compressible than a fine river sand and provides greater strength as the particles interlock.
Description: Washed sand feels fine and soft to touch. It has a very consistent particle size, runs easily when dry and is generally a white or yellowy-white colour.
Uses: Perfect for sweeping between your paving stones or in a sandpit for the kids. It’s also a component of concrete, sand cement and render mixes.
Other names: Sharp sand, beach sand, Sydney sand.
When viewed in close-up the granules of river sand are distinctly rounded from rolling and cascading down riverbeds. Because of the rounded nature of the particles, lots of tiny gaps are formed, even when compressed, and that creates one of the desirable properties of this sand – good drainage. You will find both the coarse and fine varieties are washed and clean.
Description: Fine river sand feels quite like washed sand, while coarse river sand has a fine, yet pebbly, feel. Generally both will be darker than sharp or washed sand and they have a very mixed particle size.
Uses: Coarse river sand is used as a paving base. Fine river sand is swept between pavers when dry.
Other names: Sometimes the fine form of river sand is sold as washed sand.
As the name implies this is the preferred sand of bricklayers. It has a clay component, up to 30 per cent by weight, that makes it sticky. When blended with cement and lime to make mortar, the resulting mix is termed ‘fatty’, which means it is easy to work when laying bricks, as it is compressible and oozes out of the joints.
Description: Brickie’s sand has a slightly sticky look and feel when damp and forms lumps when dry. It can leave colour on hands or clothes due to its clay content.
Uses: A major component of brick- and block-laying mortar and bagging for walls. It’s available in yellow and white to allow for different mortar colours.
Other names: Fatty sand, brick sand, brickie’s loam.
To get great results when striking cuttings, use propagating sand or a blend made primarily from this sand. Although the composition varies with the supplier, propagating sand is about 95 per cent washed and sterilised river sand with added coarser material, such as fine gravel. Don’t confuse it with propagating mix, which has extra additives such as compost and expanded vermiculite.
Description: It has large particles, like coarse river sand, with small pebbles visible.
Uses: Good for striking cuttings or as a primary component of propagating mix.
Other names: Striking sand.