Adding colourants to concrete can be a terrific way to create unique pieces of art or home/yard décor items. Concrete lends itself to many extremely versatile landscaping projects such as creating faux stones, stepping stones, and even paving stones.
If you are interested in garden statuary, than you can create many artistic statuary projects using concrete and moulds. Feel free to add some colourants to your wet concrete to give the piece a new uniform shade, faux rock look, or just to be unique.
What Types of concrete colourants are available?
Most concrete colourants are made from natural substances such as iron oxides. You can also find textural colourants such as mica flakes, quartz granules, or even glass beads to provide a textured look to your projects.
You can also find synthetic versions of iron oxides, but those run the risk of being inconsistent when you mix batch after batch of coloured concrete. Your basic choices than are natural iron oxides or synthetic iron oxides. Some people have found limited success using water-based latex paint, though I cannot imagine how long the effect lasts.
Why would you use them?
There are many reasons why people want to colour concrete. The same old grey colour of cold hard concrete can get boring. Plus, you can add value to your property by creating beautiful inlaid walkways, patios, and driveways with coloured concrete.
Imagine a patio created with the beautiful shades found in natural stone, but instead of the expense of ordering granite or flagstone, you simply make your own faux versions using concrete and a few iron oxide colourants.
Quite a few people have gotten in to the business of cast concrete paving stones, stepping stones, and patio tiles. They do this because home owners want something that is unique to their property, and they can get that from a small backyard vendor rather than a home improvement store. Have you noticed that all of those products look the same?
They are expensive too, compared to the cost of casting your own stepping stones and paving stones. Why would you not consider using colourants to help you create a product that is exactly what you are looking for?
Can you Mix colourants to create your own unique colour?
Yes, in fact, most colourants are easy to mix either to come up with a unique colour or to create a multi-coloured effect in a mould. Flag stone, for example, is often several shades of greens, gold/brown, and sometimes blue, red or yellow.
If using a mould then you can create those same shading effects that are found in natural stone by adding colourant powders to the mould after you have applied the de-moulding agent. Simply sprinkling or lightly brushing colourants into your mould will give you a beautiful, natural effect.
It is necessary to understand that concrete colourants do not create a full spectrum choice for colours. They tend to range from light tan to maybe as deep as a terra-cotta pot and from pale, mint green up to a dark green. You can also achieve yellows, browns and golds, in addition to whites and black/greys. Even ordinary shades of blue are available, but what is missing is the bright colours like red.
It is always wise to take safety as a primary concern when working with concrete and concrete additives. Use goggles to keep liquid and powdered products out of your eyes.
Concrete is a created using a chemical reaction that beings when the powders come into contact with water. A pair of goggles will help to keep your eyes free of chemical burns.
Wear a particle mask when working with dry powders such a concrete and concrete colourants which can become airborne. Your lungs are sensitive to the same chemical reaction that is found when concrete comes into contact with liquid.
Avoid damage to your lungs by wearing a particle mask. Protect your sky by wearing long sleeve shirts and a pair of industrial grade rubber gloves any time you are mixing or working with concrete.
How to use colourants:
A good tip is to make a recipe of your own colours that you create. This way you can re-create those colours if needed. You can test colours by mixing colorants with very small batches of concrete.
For example, if you are going to be making stepping stones then set up your moulds and mix your concrete. Instead of adding the colourant to the large batch of concrete, place a measured amount of concrete into a five gallon bucked, and then add a measured amount of colourant.
Make a note of how much concrete to colourant that you used. When mixed, pour into a single mould. Repeat that process until you discover the colour that you want. Once you have a recipe of the colourant to cement you can recreate that end-colour as you mix up the whole batch of concrete.
Mixing colourants: Always mix colourants (dry or liquid) in water and then add the liquid to the concrete. This will help you ensure that you have an even grade to the colour.
Mixing dry powder or even liquid colourant into the concrete (without premixing in water) will often times result in streaks and individual tiles being a different hue. Not a good outcome if you are laying concrete for a sidewalk.
Creating faux a stone look:
You can add it to moulds to create surface effects. Once the mould has been coated with the release agent, you can sprinkle dry colourant into the mould creating a “dusting” effect.
If you mix three, four or five colours that are complimentary, you will end up with a natural looking stone. Black or white is also a good colour choice if trying to create natural looking granite, feldspar, etc.
A small scale that measures in grams. A small scoop for dry colourant transfer. A measuring cup if using liquid. Large glass measuring cup/beakers are available at kitchen supply stores.
You can either mix your colourant into your wet concrete, or you can add it to moulds to create surface effects. If mixing the colourant into wet concrete, then mix the powder with liquid, and then add the concoction to the concrete mixing vessel before it is all the way mixed.