The Secrets Behind Beautiful Patinations

Patination is the attractive blue or green or brown colouring that develops over time with exposure to the elements on some metals, particularly bronze and copper. The process can occur naturally or it can be hastened and controlled to some degree. Accelerated patination has been practiced for hundreds of years – in imitation of natural effects, and also because patinated metals can look very attractive.

David Harber is probably best known for vibrant blue patinations as on the Mimeo Cascade water feature above. But we can patinate to a more natural green colour as well as a brown finish that we call antique tan which can be darker or lighter. Patinations can also be mixed for an appealing mottled effect. See below for examples.

Below, we talk to Sam Burghard, Laura Smith and Max Chawner-Davis from the Finishing Team about how they create ravishing patinated effects on David Harber's pieces.

What are the key elements behind beautiful patination?

1. Conditions

For a patination to be beautiful, the conditions need to be right. There are a lot of variables that may affect the final result: temperature, moisture, humidity, sunlight, moisture on the brush, how quickly you work, how much time is left between applying layers, contamination from other materials such as dust or sand... It is about knowing which variables will affect the patina.

With the right conditions, the patina will occur as it is meant to occur.

2. Art

There's a difference between knowing the process by following the instruction on a guide book, and having a real feel for patination.

Here at David Harber, we know what effect the different variables will have on how a patination is going to look because the knowledge is there. But it took years and years of patinating to make us experts in this art. It is one of our trade secrets.

In the past people had recipes for patination using certain compounds found in nature like stallions urine, or even drunk people’s urine! People started using these materials for door handles and other items as they tried to understand why materials like copper and bronze were tarnishing.

By trial and error and by changing the processes, people acquired the know-how we have today. But of course now we use chemicals.

So good patinations don't come from talent, but from in-depth understanding. It is a very niche knowledge that each staff member needs to learn by doing.

What are the stages you need to go through?

It depends on the finish as each finish will have a different process.

But – to use the Mantle sculpture as an example – the first stage of the patination is to sandblast the outside which is the part that gets the blue verdigris patina. The point of sandblasting is to clean and open the metal so that it accepts the chemicals. The first chemical we use acts as a base layer and it gives the piece a dark appearance; after that has dried, the second stage is to apply a chemical mix (DH secret source) which brings out the blue verdigris colours; then we buff the surface to give it a protective shine.

The whole process (plus gilding the interior) is applied to the two separate halves of the Mantle and then we join the two halves together, carefully matching the colours of the patina to hide the join.

Usually, at this stage, the weather conditions will have changed, so we need to replicate the conditions of the original patinating. So if it was raining on the first day, we need to make our environment more humid for the final patination.

What do you think are the key skills required?

Patience, time and passion. It's an ongoing process. The more you learn, the more there is to learn. The more passionate you are, the more you will learn, which helps you become an expert. With the finishes we offer, you do have master them at first. But that isn't really enough. We don't follow exactly the same process every time. You need to learn and develop your skill in order to create different and more interesting finishes.

We also need to remain humble, because the process can go wrong at any point and we need to have the drive to learn from mistakes and improve with them. Because we are manipulating natural chemical reactions, so we are never on the driving seat, we are just giving directions.

You have to remember that once we have finished the patina and the sculpture goes to the client, the weather conditions will change the finish and the look of the sculpture is going to start changing with nature. With time, the metal will do its own thing and the patina will change. That is why we seal patinated pieces with bees wax. But the natural conditions will always affect how the sculpture will look over a long period of time.

What do you find most interesting about the process?

• Max: For me, it's the fact that you can do hundreds of patination jobs and yet every time you do it, something will be different. No matter how regimented and repetitive you are, the process will differ – which is also what makes each sculpture distinct.
• Sam There is a level of manipulating the environment. All sculptures we sell have a different look to them. Even if we are making the same piece, with the same process, things will change, and the result will be unique. There is a level of awareness of your surroundings that needs to go into it the process.
• Laura: I like how each piece inspires me to do better on the next one. It reminds you of the passion you have and the will to get better and better every time. The minute you stop caring, you are in the wrong job. And your passion shows in the quality of your work.

How did you start learning about the art of patinating

• Sam: My first contact was from looking at the patinas on old copper coins, they used to all have different patinas to them. Also from looking at monuments like Still Water, Nic Fiddian-Green's iconic sculpture of a horse's head drinking, which has a beautiful patina to it. You might think that it has developed its patina naturally, but we can see it was not a natural process by rather created by man.
• Laura: Going to cities and seeing the different patinas on monuments and buildings, and proper nerding out on how different they look in their shade and textures. I've seen some pipes on a building in Budapest, which I've found quite interesting because the patina on them was very blue since almost no sunlight got to them.
• Max: In the workshop with my dad as a kid, and then by learning at David Harber. Over time, after I have learnt the basics, the team has developed our processes. There is no specific science, it has to do with the moisture in the air and we learn how it happens naturally.