Never ever wash jeans, new trend among young (2)

Experienced jeans fans examine the selvedges (nonfraying edge of the fabric) to see if the denim is made using the original techniques, that is, using old-fashioned shuttle looms.

Good raw jeans use long-fiber cottons produced in America, Zimbabwe, Egypt and other places with abundant sunlight. Their beautiful indigo color is achieved by dying multiple times.

All these processes will give the jeans a very plastic quality allowing them to be shaped and worn out as you want.

Modern pre-washed jeans are shrink-proofed, but not the raw ones. So buy one or two sizes larger than your original measurement.

With the best raw jeans as time goes by, the areas behind the knees can form natural wrinkles and color-fading. These are called "honeycombs" for the resemblance. The crotch area will form some radial wrinkles too, which are called "cat whiskers."

But the special requirements and high-standard craftsmanship make those raw pants expensive. Lee, Levi's, Evisu and some other expensive brands produce the best raw jeans for people to choose from.

Among Yang's collections, there are 100 pairs of Evisu jeans, with each pair costing more than 2,000 yuan ($321.4). Yang's digital bill shows that in 2012, he spent about 270,000 yuan online in purchasing raw jeans.