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Which kind of hide should I choose?

We are often asked what is better – Horsehide or Steerhide? While some people will swear by one or the other, the truth is that both result in stunning, high quality leathers. Each has slightly different properties which may or may not be important in making your decision. Again, these are general rules of thumb – there are many other factors that account for the properties of any given leather:


In the 1980’s, we led the way in reviving the use of Horsehide for leather jackets – a material scarcely used since the early-mid 20th century. Over the years, Horsehide jackets and Aero have become synonymous, and it’s still accounts for the majority of jackets we make. Generally, although the skins are a bit lighter and less thick, Horsehide has a denser fibre structure than Steerhide. This tough composition makes it more resistant to stretching and abrasion, therefore taking longer to break-in. The follicles on a horse are also smaller meaning it’s a bit more water repellent than Steerhide. It usually has a slightly coarser, but less prevalent grain with a lot more variation than Steerhide, although the Front Quarter Horsehide we use is more consistent than skins from other parts of the animal.


Steerhide/Cowhide is the most widely used leather throughout the world – it’s readily available with a large useable area and is very versatile. Relative to Horsehide, skins of the same weight category are a bit heavier and thicker (although not always the case), however it usually takes less time to break in than Horsehide due to its less dense fibre structure. It normally has consistent grain throughout the hide which is more pronounced than Horsehide and which develops beautifully with age.


Not to be overlooked when deciding your leather – especially for those looking for the toughest leather they can get without the need for a long break in! It is very breathable, yet has amongst the best natural water resistance properties of any hide (which is why most Navy jackets were made from Goatskin). Compared with Horse and Steer, Goatskin develops/ages more slowly although still has the potential to yield a beautiful patina with a lot of wear. As tough and durable as Goatskin is, it is very soft to the touch and is remarkably supple compared to most Horsehides and Steerhides, so it’s incredibly comfortable to wear straight away and requires very little break in. It almost always has a very pronounced ‘pebbled’ grain which really adds to the unique feel and properties of this leather.

Can I get samples of leathers sent out?

Yes, there is a listing to request leather samples here.

You can order a maximum of five samples per order and there is a small charge per sample with postage payable on top of this cost.

What is ‘full-grain’ leather and why choose it?

The leathers we use at Aero are top grade ‘full-grain’ leathers. ‘Full-grain’ doesn’t necessarily refer to the amount of grain you can expect in a hide, but it refers to which part of the hide is used and how it is processed before tanning.

While full-grain leather uses the entirety of the uppermost grain layer of the animal’s hide and goes straight into the tanning process without any further treatment after hair removal, lower grades (which make up the vast majority of leather in the world) use different parts of the skin and have additional processing carried out beforehand.

“Top-grain” leathers for example (the next grade down from full-grain) have often been sanded down to create more surface uniformity and increase workability with the leather, giving a manufacturer a fresh top surface to apply a variety of finishes. While top grain leather can still be high quality and is used to produce many high-end luxury goods, the future patina and durability of the leather is compromised in the process of removing the very top layer of the skin.

‘Split’ leather is an umbrella term for most of the leather in the world which is created from inner skin layer (the corium) after it is split from the top grain layer. This kind of leather is more pliable and versatile than full grain leather and can be processed in a variety of ways such as artificially embossing grain (known as corrected-grain leather). While still advertised as “genuine” leather, these leathers are of lower quality, durability and they lose their natural beauty, feel and development potential.

But because the entire thickness of the skin is used in full-grain leather, it’s a lot stronger and more durable than leather that has been ‘split’ or ‘shaved’ and because all of the original characteristics of the leather and oil absorbing properties are retained from the uppermost layer of the skin, the leather will develop a beautiful natural patina over time. Because they retain this natural beauty and impressively withstand the demands of time, and because only the best hides can be used due to their authentic unprocessed nature, full-grain leathers come with a higher price tag than other grades, but one that is definitely justified by the end result.

What is ‘midweight’ leather’?

For decades we’ve been traditionally associated with ‘heavy’ leather jackets made from Horween’s Chromexcel® Leather, but we also carry a wide range of lighter leathers that are generally categorised as ‘midweight’ leathers.

Please note, while we categorise these leathers as ‘midweight’ and ‘lighter’, this is relative to Chromexcel® which is a particularly heavy leather. Many of these leathers are still heavier than high street leathers many are accustomed to, and we can guarantee they are more substantial and higher quality (almost no high street leathers are full-grain).

While some people may adopt a ‘heavier is better’ attitude towards leather, as long as the leathers being compared are full-grain, weight is not really indicative of the ultimate ‘quality’ of a leather – it’s simply one attribute (albeit an important one) to consider when making your leather choice.

‘Midweight’ leather will be easier to wear, taking less time to break in and may be more appropriate for warmer climates, whereas a heavier leather may be better suited for a motorcycle/winter jacket for added protection and those who want to really feel the weight of their jacket on their shoulders and don’t mind a long break-in period.

The spectrum of weight runs from our lightest midweight leather ‘Battered Steerhide’ with a general weight of 2oz, to our heaviest leather, Horween’s ‘Chromexcel’ Steerhide with a general weight of 4oz.

However, these categorisations are a very general guide - there is quite a bit of variation within the midweight category (Vicenza wears quite a bit heavier than Battered Steerhide for example) and even within the same leather, because the leather is full grain without any leather splitting, different hides of the same leather can vary in thickness and weight.

What is leather tanning?

Tanning is the process of treating and preserving hides (from larger animals) or skins (from smaller animals) to produce long-lasting useable leather.
Hides and skins are usually either ‘Chrome Tanned’ or ‘Vegetable Tanned’ (or a combination of both) to produce leather.

Vegetable Tanning

Vegetable Tanning was the original (and up until the 19th century, the only) method of producing leather. For thousands of years, our ancestors developed and used variations of the same basic process to turn their raw animal hides into essential long-lasting leather and while modern methods are more refined and scientific, the main principles remain the same.

Vegetable tanning involves the use of tannin, a naturally occurring compound that is found in plant sources like bark, roots and leaves. A hide is stretched on a wooden frame and over time, soaked in an increasingly concentrated solution of these plant extracts/tannic acids. The tannins displace water molecules bound to the hide’s collagen (it’s main structural protein) and take the place of the removed water. The process is long and complex, taking anything between a few months to a few years and requiring the work of highly skilled craftsmen to ensure the tannin molecules replace the water molecules in just the right way to produce durable and well preserved leather. Because of the skill and time involved in its production, Vegetable Tanned leather is rarer than Chrome Tanned leather – only 10% of leather produced is Vegetable Tanned. This natural tanning process is also relatively environmentally friendly (although it does use a fair amount of water).

Chrome Tanning

Vegetable Tanning’s production time, complexity and expense and the industry demand for a more time-efficient and less costly solution led to the development of ‘Chrome Tanning’ in the mid-19th century.

The basic tanning principle is the same: to remove and replace water molecules from the collagen of the skin. However, Chrome Tanning replaces the water with chromium salts instead of tannins.

The process involves placing pre-treated hides in baths and drums that contain the chromium sulphates as well as acids and other chemicals which ensure the chrome better fits in between the collagen molecules, before returning the hides to a normal pH level.

It’s quicker turnaround, durability, and the huge variety of leathers with different properties that could be made with Chrome Tanning saw it quickly become the world’s preferred method of tanning, allowing leather to become a staple in almost every clothing genre – from everyday workwear to large military contracts during the WW2 period. To this day, around 90% of the world’s leather is Chrome Tanned.

It does however have a far greater environmental impact than Vegetable Tanning, although over the years as this impact was better understood, many tanneries are now subject to strict environmental regulations and take measures to reduce this impact (the Chromexcel® leather that we get from Horween in Chicago being a good example).

Combination Tanning

This method involves some combination of Chrome Tanning and Vegetable Tanning and seeks to strike a balance by capturing some of the advantages of both individual methods. Some of our leathers like Kelpie and most famously, Horween’s Chromexcel®, have their own methods of combination tanning (mostly Vegetable Tanned with a quicker final Chrome Tannage to help lock in the waxes and colour).

So which method produces the best leather – Chrome Tanning or Vegetable Tanning?

Although some have strong individual preferences for one or the other and either method may produce more ideally suited leather depending on the situation and buyer, neither method produces inherently ‘better’ leather – just leather with different properties. Speaking very broadly, Chrome Tanning allows for softer and more supple leather (with relatively less breaking-in required) which is more resistant to the elements and will retain colour consistency for longer. It won’t patina as fast or to the same degree as Vegetable Tanned leather.

Vegetable Tanned leather’s organic nature means it patinas more quickly and dramatically, reacting to exposure to the elements more than Chrome Tanned leather. Although stiffer and firmer to begin with, Vegetable Tanned leather’s hand and feel also develops substantially, softening up or ‘breaking in’ with wear. Chrome Tanned leathers also go through this process to varying degrees, but often don’t develop as much in this regard or require as much breaking in.

Many consider Vegetable Tanned leather as more desirable than Chrome Tanned leather because of the general increase in the time and skill required to produce it. While often true, this can be a misleading generalisation. While it’s true that because it’s faster to produce, many (but not all) lesser quality leathers are likely Chrome Tanned, this does not mean all Chrome Tanned leathers are lesser quality. Some of the best quality leathers we’ve worked with over the years have been Chrome Tanned. Like everything, there is a spectrum of quality in the leather produced using each method and rest assured, we only use the very best from each.

What really matters is what you’re looking for from your leather – do you want a Vegetable Tanned leather’s ever-developing story that its gorgeous patina tells over the years? Or is a Chrome Tanned leather’s suppleness and relative consistency more important to you? In any case, the tannage is just one factor in determining the properties of any given leather. The type of hide, it’s weight and the method of finishing the leather are just some of the other factors which determine a leather’s properties.

What is the difference between aniline and semi aniline leather/finish?

Leather dyes penetrate and are in the leather, accentuating the natural variations in the hides (some areas perhaps being darker and lighter). Leather paints/pigments on the other hand, coat the fibre and are on the leather.

Aniline leather is leather which has been dyed but has not received any pigment in it’s finish. This approach is for the purists who want the most authentic look from their leather, where as much of the original hide’s character and variation is retained as possible. The leather may be afforded some protection by its fully translucent finish, but it is more susceptible to the elements and markings/fading over time than semi-aniline leathers (which is what gives these leathers their beautiful patina). Aniline leathers that we use include ‘Badalassi’ Steerhide, ‘Kelpie’ Horsehide and Horween’s Chromexcel® leathers.

Semi-aniline leather is also aniline dyed, but it’s finish also incorporates a small amount of pigment on the leather (but not so much that it conceals the hide’s natural characteristics). This approach allows for a more consistent colour throughout a hide, as well as more protection from fading and marking over time while still retaining much of the hide’s natural beauty, although the trade-off is that a small amount of the original hide’s character and natural development is sacrificed for this consistency. Semi-aniline leathers that we carry include ‘Vicenza’ Horsehide and ‘Jerky’ Horsehide.

How is your leather sourced?

Our hides are sourced from animals as a by-product of other industries (not killed for their hides).