These potholders were made using Peaches & Creme worsted weight cotton yarn in an ombre colorway known as "shaded denim." This variegated yarn features contrasting colors of blue and off-white. The cone of yarn is pictured on the upper right.
The potholders are crocheted using afghan stitch, also known as Tunisian simple stitch. The edging is single crochet, with a final round of slip stitch.
The lower photo is a close-up view of the stitches.
This particular combination of pattern and yarn did result in a bit of color flashing. See how the darkest blue forms some obvious diagonals that combine to create a sort of zigzag?
If you don't like this effect, it's probably best to avoid using this particular yarn with the potholder pattern I've linked. You aren't limited to using variegated yarns - the pattern does looks great when made with solid-colored yarn as well.
On the other hand, if you like the idea of being able to create an interesting patterned look without having to do any color changes whatsoever, perhaps you'd enjoy crocheting this project as shown.
Overall, I thought this was an interesting project to crochet, and I like the end result.
Coordinating Dishcloth Pattern:
These potholders are part of a matched gift set which also includes a variegated denim dishcloth.