[The Quintessential Leather] A Comprehensive Guide to Types of Cowhide — What Are the Differences Between Calf, Kip, Steer, Cow, and Bull?

Cowhide is said to account for approximately 80% of all leather products. However, the term "cowhide" actually encompasses five distinct types—categorized by the animal's age and gender—each with significantly different characteristics.

In this session, we will explain the differences between them while looking at actual leather samples.

Cowhide can be broadly categorized into five types.

Cowhide is classified into the following five categories based on the animal's growth stage and condition.

• Calf (under 6 months old)
  
• Kip (aged 6 months to under 2 years)
  
• Steer (over 2 years old / castrated male)
  
• Cow (female, over 2 years old)
  
• Bull (3 years of age or older / uncastrated male)

Let's take a closer look at each of them.

1. Calfskin — Rare and beautiful calf leather

This leather is obtained from calves under six months of age. Since there is little custom of consuming veal in Japan, the supply of the leather—a byproduct—is limited, making it a rare material.

The most distinctive feature of calfskin is the unique wrinkle pattern known as "tiger stripes." This pattern arises from the natural grain texture found only in young calves, creating a soft and beautiful appearance on the leather's surface.

In terms of size, a single whole hide typically measures between 70 and 100 decisi (where one decisi is defined as a 10cm x 10cm area). Domestically produced calfskin averages around 80 decisi, and four to five hides are generally used to make a leather jacket.

A major advantage is that, because the entire piece of leather is small, you get a uniform appearance regardless of which part is used.

2. Kip — Leather from medium-sized cattle that retains characteristics of calfskin.

This is leather from cattle aged between six months and two years. It is also known as "medium cattle leather."

While calfskin is typically distributed as whole hides, kipskin is most often sold as "sides"—hides split in half down the center of the back. A single side measures approximately 120 to 140 decisi.

As the cattle are still young, the "tiger-stripe" fat patterns—a characteristic remnant of calfskin—remain clearly visible, particularly around the neck area. With few blemishes, the leather is said to possess a fine grain second only to that of calfskin.

3. Steer — The most widely available standard type of cowhide.

This is leather from a male cow that was castrated between the ages of six months and one year and is over two years old. It is the most widely used type of leather for cowhide products.

A major advantage is the large usable surface area; a side of leather typically measures 200–250 decimeters, with larger ones reaching around 300 decimeters.

However, due to its large surface area, the appearance of the leather varies significantly depending on the specific section. For this reason, each section is given a name and utilized according to its intended use.

[Main Cuts of Steer Beef]

• Shoulder (neck to shoulder): Thick and heavily wrinkled, with a rugged appearance. As this area is subject to frequent movement, the leather is used in products that showcase these distinctive wrinkles.
  
• Bend (lower back to rump): The smoothest and most fine-grained section. It is frequently used for products requiring an attractive finish, such as belts and wallets.
  
• Butt (rear section): Dense, firm leather. Features a smooth surface, similar to the bend.
  
• Belly (abdomen): The leather is thin and the fibers are looser. It is often used for linings and the like.
• Double Shoulder: A piece cut specifically from the shoulder area of a whole hide, rather than from a side (half-hide). It is characterized by a bold, distinctive appearance featuring pronounced neck wrinkles and fat deposits. Due to its thickness and high density, it is frequently used for items such as leather jackets.

4. Cow — Cowhide

This is leather from a female cow aged two years or older. While its basic characteristics do not differ significantly from steer hide, the fibers in the leather around the belly area may be slightly looser due to the effects of giving birth.

For this reason, steer leather tends to be used somewhat more frequently for items such as clothing.

5. Bull — The toughest and most rugged leather

This is leather from an uncastrated male bovine aged three years or older.

With an original thickness of 3 to 5 mm, it is the most durable of the five types. However, because the animals are not castrated, the hide is prone to scratches—often caused by fighting with other cattle—and has a coarser grain.

Just as wrinkles increase with age in humans, these hides feature pronounced, fatty-looking wrinkles around the neck and belly areas. They typically measure around 250 decisi.

Bull hides may also bear brand marks, which are particularly common on leather from overseas.

Summary

The characteristics of cowhide vary significantly depending on the animal's stage of growth—ranging from calf, kip, and steer (or cow) to bull.

• The younger the leather, the finer its grain and the softer it is.
  
• The more mature the leather, the larger its surface area and the greater its durability.

Furthermore, the appearance varies depending on the specific part, and different sections are utilized according to their intended use.

While these differences serve as a key guide when selecting leather, at STRUM, we view them not in terms of superiority or inferiority, but rather from the perspective of how best to bring out the unique character of each type.

Even with the same cowhide, the final result varies significantly depending on which part of the hide is used and what kind of processing is applied.
It is only when the unique character of the leather itself and the maker's intent converge that the product achieves true perfection.

When choosing leather products, it is of course important to know what type of cowhide is used,
How is the leather treated, and what kind of finish does it have?

By looking that closely, you should be able to gain a deeper understanding of the product's essence.

Please take a look at the difference for yourself in the actual product.