One of our strongest, non negotiable core brand messages that forms the backbone of all of the footwear that we make, is to only ever work with the best possible materials available for the specific collection or style in question. This means continual sourcing, development and research and more than the occasional trip to the local leather merchants.
When we find the material that we feel is suitable it’s then time to make some samples so it can be worn and trialled in the real world. This part of the process will normally separate out any suedes or leathers that we feel are not of the quality that we require and then we’re ready for full production.
Over the years, we’ve narrowed down our selection and we’ve become quite loyal to a handful of tanneries led by the world famous Charles F Stead tannery in Leeds, England who were founded in 1904, and the Horween Company from Chicago, USA who were founded in 1905. Tried and tested is normally a good way to go and with each of these companies having over a century of trade under their belts much like our own company, we're more than happy to form longstanding relationships and supply lines.
Proven history and heritage is one thing, and continuous use and trialling of a leather will normally raise any flaws or weaknesses, but what if we wanted to look deeper into the materials that we use so that we really know what we’re dealing with - on a scientific, molecular and downright geeky level. Well, that’s when being located in the heart and sole (pun intended) of the leather and shoemaking industry, otherwise known as Northampton, comes in very handy.
Introducing the ICLT or Institute for Creative Leather Technologies. A purpose built facility located in the recently opened University Of Northampton, the ICLT is a world class research and educational facility. It offers fully qualified university degree courses alongside industry leading professional courses. Filled with highly technical equipment and laboratories that allows leather to be tested at degree level and for commercial use and investigation across several different categories including fashion and the automobile industry. This world class, one of a kind operation even houses its own fully functioning tannery on site, where they have the capability to process from raw material right through to finished leather product.
With all of this powerful leather tech equipment nearby, we wanted to put the materials we use under the microscope - a high powered Leica M205 C Stereo Microscope specifically - to find out what it's really made of and what the quality really looks like in terms of structure and grain.
At this point we're starting to get out of our depth with regards to the science of it all, so we handed over some leather swatches to our guide for the day, Senior Lecturer and all round leather expert - Marc Gummer. Marc's extremely knowledgeable about all aspects of leather having either studied, worked or taught on it for most of his adult life.
Moving into a clinical, white walled laboratory, Marc finely sliced a sample of each leather into cross sections with a razor blade and scalpel. He explained that the aim is to get the cut as clean as possible so that the most detail can be brought out when viewed. Each section was then attached to a glass slide so that the top side and direction of the grain could be analysed under the Leica microscope at x35 magnification.
The resulting images are strangely fascinating as you don’t ordinarily get to take such a detailed look at leathers right down to the fibre and individual grain level. Marc was kind enough to write us some detailed notes of the analysis processes from the day, along with his expert thoughts on the findings of the individual leathers. So, now it's best if we hand over to Marc's direct notes below for the more scientific and investigative part of this blog:
Marc Gummer notes
All images are taken at x35 magnification. A cross sectional image and image of the leather surface have been taken. When observing the top surface of the leather we are looking for evidence of natural characteristics such as hair follicles or the coating applied to the surface.
The more natural the leather surface, then the more likely we are to be able to see the hair follicle pattern. Most leather will have had some surface treatment or surface coating to give protection or enhance the appearance and provide colour. This can sometimes obscure the natural characteristics.
When observing the cross section we are looking for a good interwoven fibre structure. It is the structure which gives the leather properties such as strength and flexibility. Damage to the fibre structure can be sometimes observed under the microscope and we can observe problems such as looseness.
Typically we are looking for a tight, dense interwoven structure. Gaps and spaces can be evidence of looseness and potential weakness. However softer leathers may have a more open fibre structure to give them the softness and flexibility.
We often refer to grain ‘break’ – this is the creasing observed when we fold, or curve the leather with the grain inward. If the leather remains smooth with no creases then we refer to this as good break or fine grain. If the leather becomes wrinkled on the inward crease then this is referred to as poor break and is linked to looseness.
Box Calf
From the image of the surface we can see the hair follicles, but they are less defined, showing that there is more surface coating. This is likely to be due to the leather being white. To get a clear white colour we normally need to apply a coating containing pigment. The more coating that is applied then the more the hair follicle is obscured. The fibre structure appears very dense and tight, we can clearly see the interwoven fibre structure. This tight structure gives the leather its firmness which allows it to maintain the structure when making footwear.
Crown Northampton notes:
We searched long and hard before deciding to upgrade our core leather from calf to box calf. We wanted a consistent material that held its colour, didn’t crease too much, was durable and softened over time. Box calf is seen as a higher grade of calf due to its firm, consistent finish and fine grain. For this reason it is the material of choice for most high end shoemakers and gets better with wear. We source from a very well respected European tannery that purposely look after their livestock so as to improve the overall quality of the end products.
View our box calf collection here
Kudu Leather
Known for the natural characteristics on the grain surface caused during the life of the animal. From the top surface we can see the grain is slightly undulating but the hair follicles are visible in between. It has a waxy coating but generally appears quite natural, allowing the natural feature to stay visible. The cross section of this looks interesting we can clearly see the grain layer (dense layer under the surface) and corium (lower portion where the fibres are bigger). Very nice tight interwoven structure to give strength, but not as dense as some of the other materials showing it it likely to be more soft and supple.
Crown Northampton notes:
Sourced directly from C F Stead in Leeds, England, kudu leather has a unique finish that makes each hide individual full of character marks and detail picked up on its journey through the African Plains. Supple, durable and a great alternative to box calf leather.
Kudu Suede
This article is made on the reverse side of the leather (flesh at the top and grain down). From the image of the surface it is possible to see the open fibres which we refer to as the nap. It is the exposed fibres which give suede its distinct tactile nature and soft touch. In the cross section you can see the grain side to the bottom with the flesh side at the top.
Crown Northampton notes:
Extremely soft yet also very durable. Our kudu suede is also sourced from C F Stead and is a popular choice when looking for something a little different, the Snuff suede in particular.
Horween Cavalier
From looking at the surface there is very little of the natural characteristic (hair follicle) visible. The leather has a waxy coating which gives depth to the surface appearance. It also has a pull effect from the waxy coating. The leather is not fully dyed through which also adds do the depth and the pull up effect. The fibre structure is in good condition – tight and interwoven, giving the leather strength and avoiding looseness.
Crown Northampton notes:
Shown here in Ink which is is one of our best selling colours, Horween Cavalier is also available in Sunflower which is a class light tan colour. Very similar to Horween Chromexcel, it is a pull up leather that changes if the surface is rubbed or your finger is pulled along the underside of the leather. The finish naturally develops over time and is personalised to the wearer.
View our Horween Collection here
Horween Chromexcel
Similar to Cavalier in that there is very little of the natural characteristic (hair follicle) visible. The leather has a waxy coating which gives depth to the surface appearance. It also has a pull effect from the waxy coating.
Crown Northampton notes:
Chromexcel is one of Horween's most recognisable and well known leathers. It contains a secret Horween family blend of oils and greases that give it a truly original handle which is packed full of character. A pull up leather like Horween Cavalier, Chromexcel starts firm then softens to mould to the wearers foot. Very durable.
View our Horween Collection here
Finest Calf
Calf leather is known for it’s fine grain and tight fibre structure. Young calf is seen as a more refined article but can be more delicate in nature that leather from more mature animals From the images, we can see the hair follicles clearly on the grain surface, but it appears that there is a light surface coating (for colour and protection). Younger animals have finer hair and therefore smaller hair follicles which makes the grain surface look smoother and is sought after for refined leather articles. The cross section shows a good tight fibre structure. It is the tight fibre structure that gives calf the fine grain ‘break’ (smooth grain with lack of creasing/wrinkles).
Crown Northampton notes:
The finest vegetable tanned calf that we use and one of the very best available on the market. This was the first material we chose for our premium Hand Stitch Collection. Soft, yet firm and strong, veg tan calf uses high quality livestock so the grain is very fine with a great handle. A very supple, luxurious and durable leather.
View our Hand Stitch Collection here
Horween Buffalo
Buffalo is known for its grainy appearance and strength. From looking at the leather surface we can see the hair follicles very clearly indicating that the leather is very natural. We can also observe the undulating surface showing the grainy appearance. The cross section shows that the leather is thicker than many of the others. The fibre structure is not as compact as the above leather, suggesting the leather is softer and more flexible (and potentially more stretchy?). While the fibre structure is not as dense, it is not too open and looks in a good condition.
Crown Northampton notes:
Horween buffalo displays a pronounced grain giving it a stand out look and appearance. The skin size is shrunken down when processed and it is also olive oil tanned. All of these combined stages result in a hardwearing material that is soft and supple with rugged good looks. Selected for the Hand Stitch Collection due to its high quality.
View our Hand Stitch Collection here
Deer Suede
This article is made on the reverse side of the leather (flesh at the top and grain down). From the image of the surface it is possible to see the open fibres which we refer to as the nap. It is the exposed fibres which give suede its distinct tactile nature and soft touch. It was commented on during analysis that it looks like carpet and it actually is quite similar in the fact that it is lots of fibres with the ends exposed that give it the soft feel. In the cross section we can see the grain downward with the fibrous flesh side at the top. You can also see that the flesh side looks quite ‘open’ compared to the middle which looks quite dense. It will have been treated (maybe tumbled and buffed) to open the flesh side to enhance the nap. Deer is known for being quite stretchy and supple.
Crown Northampton notes:
Sourced from Barrhead in Scotland, the deer we use has an extremely luxurious handle yet wears very hard and is unexpectedly durable. Once again, these premium quality characteristics made it an easy selection for our Hand Stitch Collection. Very soft and very strong.
View our Hand Stitch Collection here
Horween Shell Cordovan
Typically made from horse, in particular a region from the butt area known as the shell (meaning a small area is available for each hide. The fibre structure in the shell area is very dense and is different from most leathers in that it is finished on the reverse side of the skin. From looking at the surface image, it is possible to see that there is a transparent coating and that the fibres are visible. It is a very natural looking and unique leather. The cross section shows the very dense tight structure. This gives the tight structure needed to make footwear and hold its shape.
Crown Northampton notes:
Shell Cordovan is the jewel in Horween's Crown and is thought of by many to be the very best leather in the world. Quite simply, there's no other leather quite like it that it can be compared to and if cared for correctly it can last a lifetime. Known for its unique characteristic of rippling not creasing due to its tight firmness and genetic make up. Due to the small shell batches that Cordovan is made in and continuous high demand, supply from Horween is always limited and distribution to shoemakers is very selective. High gloss finish.
View our Hand Stitch Collection here
We hope you enjoyed that scientific deep dive into the leathers we use and understand our passion and commitment to only working with the very best materials available.
We'd like to say a big thank you to Marc Gummer for his time and expertise and also to the ICLT for having us.
More information on the work they do at the ICLT and the courses they offer can be found here.
