90% of the world’s leather actually isn’t the kind that gets better as it ages (that beautiful "patina" effect people often talk about). These days, most leather is made using a process called chrome tanning. While this is a faster and cheaper way to treat leather—and it can produce vibrant colors and a soft touch right off the shelf—chrome tanning uses toxic chemicals that are harmful for the environment and the resulting leather doesn't have those authentic qualities that makes the material so beautiful and long-lasting.
Wolly made uses premium vegetable tanned leather from Wickett and Craig, one of the last vegetable tanneries in the U.S. "Veg tanning" is the authentic, age-old process of treating leather with organic tanning agents, such as oil from tree bark or other plant material. This process is designed to make the material more durable and resilient. And the best thing about vegetable tanned leather is how it ages. Every wallet develops a unique patina from its user. After a year or so, no two wallets look the same , you earn your unique style and patina over time.