The word “cordovan” is often used incorrectly to refer to any burgundy-colored leather. Shell cordovan actually encompasses a variety of colors, and it's also a rather specific kind of leather. Whereas being a horse’s ass in social situations indicates obnoxious behavior, being a horse’s ass at the Horween leather tannery indicates raw potential. After a 105-day tanning process, hides from the backsides of horses leave Horween as some of the most in-demand leather on earth.
The butts of equine animals—mostly horses, but also mules and (as we’ll see later) zebras—include a membrane that makes the leather especially hardwearing. Cordovan wears better than other leathers, which explains why so many of the cordovan items in the Horween archives still look good despite their age. It also explains why, despite accounting for only 10 percent of all Horween leather, shell cordovan is arguably the tannery’s most famous product.