It's also why many jeans are blue on the outside but white on the inside. Each pair of jeans requires 3-12 grams of dye. Each year, we produce several hundred thousand tons of indigo dye.

Spoiler alert: It’s not because blue matches everything (though it kinda does). “Blue jeans are blue because of the unique dye used,” says textile scientist and denim expert Melanie DiSalvo.

Because old blue jeans stay strong even as they get more comfortable, they were the favorite trousers of many laborers in the 19th century. Most jeans are made with synthetic indigo dye today, ...

Blue jeans close-up. Photo courtesy Mark Michaelis via Flickr. Cut to the Gold Rush. In 1873 Bavarian entrepreneur Levi Strauss teamed up with Latvian tailor Jacob Davis to produce indigo-washed ...

Blue jeans, one of fashion’s most classic wardrobe staples, also happen to have one of fashion’s biggest environmental footprints. Billions of denim garments are produced each year, with the ...

As jeans transitioned from workwear to fashion staples, their association with blue deepened due to cultural factors. In the mid-20th century, blue jeans became a symbol of rebellion and youth ...

Blue jeans celebrate 150th anniversary It's hard to imagine a piece of clothing that's more wrapped up in American history and mythology than blue jeans. They were invented 150 years ago.

Blue jeans through the years — To this day, blue jeans remain the uniform for cowboys young and old. Here, Bruce Beasley and his grandson load cattle on their farm in Patricia, Alberta, in May 2013.

On May 20, 1873, Levi Strauss and Jacob Davis received the first patent for blue jeans. Within a century, they were a global fashion staple.

Blue jeans through the years — To this day, blue jeans remain the uniform for cowboys young and old. Here, Bruce Beasley and his grandson load cattle on their farm in Patricia, Alberta, in May 2013.