Understanding the Changing Appearance of Leather

Leather is a natural material made from the hides or skins, of different animals. Leather ‘ages’ over the years, which means its appearance changes with time and use. What forms on quality leather is called a ‘patina’, which is seen as very desirable by leather lovers because it is a hallmark of leather quality and an appealing characteristic of the material.

While most of the changes in leathers appearance are usually sought after, there are some changes that are less appealing and can often become an issue for leather buyers.

Why Leather Cracks

The most common issue is cracked leather – something which is the result of dried out or poorly cared for leather. Leather has thousands of small pores on its surface, which release and absorb moisture depending on the surrounding humidity levels. If the humidity levels are too low, the leather can dry out and cracks will develop. It’s a good idea to condition the leather to keep it moisturised and supple, further protecting it from cracking.

Why Leather Turns White

On the other end of the spectrum, if humidity levels are too high, mould can start to form on the surface of the leather. The mould often has a green or white colour and a dusty, speckled appearance. This is often confused with spew, also know as “fatty bloom”, which is the result of fats/oils from within the leather crystallising on the surface when they meet the air. Spew can make the leather look patchy with white areas or even green spots.

Why Leather Turns Green

Leather can also become discoloured and turn a greenish colour if there is an issue with faded dye. Black dyed leather often discolours with greenish patches if it fades which can happen when exposed to direct sunlight for prolonged periods of time.

Why Leather Gets Sticky

Another issue leather buyers may face is that leather can sometimes get sticky, and is common among patent and bi-cast leather products due to their heavy finishes. Stickiness on leather can happen due to a number of things:

• High humidity levels – can cause the leather to feel clammy or sticky.

• Improper tanning – the process involved in tanning leather removes salts from the hide, and adds certain chemicals. The natural pores on the surface of leather may be clogged with waxy residue left over from improper finishing/tanning.

• Dirt build up – natural oils and dirt can build up on the surface which can cause it to go sticky; this is why it’s important to keep a good level of maintenance and cleaning with your leather. Having said that, it is important to use the correct cleaning products for your item as using incorrect cleaning products can further break down the top surface and give it a sticky feeling.

The Smell of Leather

Different items of leather can smell different or have a stronger ‘leather’ smell than the next because of differences in the tanning process – all of the dyes, treatments and chemicals soak into the pores of the hide and leave their own smell; some leathers don’t have much of a smell to them at all. Leather breathes and gives out the faint smell of the animal hide.

The smell of the leather should fade over time if it is a little overpowering at first – a lot of people enjoy the smell of leather and take it into consideration when judging the quality of it.

Bad smells often come with cheap leather or poorly tanned leather – residual tanning agents and chemicals, which have not been correctly rinsed off, often leave behind a strong and unpleasant smell. Goat and camel leather in particular have a strong natural odour, which some customers may find unpleasant.

Leather can also soak up strong odours such as smoke, food odour, perfume or even mildew and mould, which has a stagnant and musty smell.