You may have heard of the term "chrome-tan," "veg-tan," or even "oil-tan". Let's break down what these terms really mean and if there is a superior tanning method. We will go over each tanning process and its use cases as well as an unbiased comparison. 

Vegetable Tanning

When we think of the word "leather," we think of a thick, durable, and rigid piece of cow hide. Imagine a saddle or an old leather belt. This is what we call "vegetable tanned leather". To give a basic explanation of this tanning method, it first starts off as a rawhide from any animal that has had its fat, connective tissue (collagen), and hair removed. It then undergoes a soaking treatment in a solution of various different tree barks and plants before it is stretched and dried. This process stabilizes the  To finish off the leather, a blend of oils and waxes are applied to the surface for protection and then the leather may be dyed or tumbled. Fun fact: the word "tanning" comes from the tannins present in the tree bark, which is what is responsible for the pickling process. This process from start to finish takes roughly 30-60 days. The result is a beautiful piece of leather ready to be made into your desired leather product. 

Chrome Tanning 

The process is similar to vegetable tanning where the rawhide is soaked, however,  instead of natural tannins preserving the hide, chromium salts are used instead. The result is a finished leather hide that takes only 1-2 days from start to finish, as opposed to a 30-60 day process for traditional vegetable tanning. A variant from chrome tanned leather is oil-tanned leather which is just the chrome tanned leather process but it undergoes an oil bath and hot wax stuffing process. This allows the oil-tanned leather to be even more water resistant. 

Vegetable Tanning vs Chrome Tanning Comparison 

We can see why vegetable tanning is considered to be better. It creates a more appealing leather and has a lower impact on the environment with its only caveat requiring more care and maintenance. In a fast paced society where time is the most valuable resource, we should not be surprised that chrome tanned leather takes center stage in being what most people experience in a leather product. Although it is faster to produce, chrome tanned leather products will not develop as rich a patina, can generally feel cheap, and will need specialized disposal to prevent groundwater contamination from toxins present from the production process. 

Strengths and Weaknesses

You may have heard people say that veg-tan leather will always be the better leather but like most things in life, the answer is not always black and white. There is an obvious consideration during its production process, however, the leather that is produced at the end serves totally different purposes. Let's break them down. 

These use cases are quite specific and can not be interchanged easily. For your favorite leather jacket, you must go with a chrome tanned leather, and for a belt, veg-tan. This is because chrome-tan leather is more predictable than veg-tan. A jacket requires large panels of flawless, supple, and water resistant material. Think of this more acting like a fabric than leather. Veg-tan leather can be more unpredictable. It might crease, take up water/ oil, or be far too rigid for something like gloves or a jacket. There are, however, slight exceptions to the rule.  Horween's Chromexcel leather, for example, is chrome tanned at its base and then vegetable re-tanned and hot stuffed with waxes and oils. This creates a leather that can develop a nice patina and behaves a little like a fully vegetable tanned leather. On the other hand, vegetable tanned leather can be tumbled and milled as well as stuffed with oils and waxes to create a soft, supple, and water resistant veg-tan leather. These leathers can only mimic specific qualities in its leather and are not complete substitutes for a tanning method. 

Verdict

I've created products with both chrome tanned and vegetable tanned leather and like most leathercrafters out there would say, is that there isn't a true superior tanning method. Although vegetable tanning is much more sustainable, there will always be a use case for chrome tanning because each leather does its own job very well and will continue to do so unless a new tanning method is discovered in the future. This entry is not created to put down one leather vs another but to simply provide some education on your current leather product and guidance when purchasing your next leather product. Of course, your enjoyment out of your leather product comes from you and these rules, just like a veg-tan, are not always so rigid.