It is not easy to say what and how much yarn I used.
Just collected lots of odds in my stash, organized them by color - light to dark and went on.

Held 4 ends of yarns and crocheted in the round with hdc stitches, periodically changing one strand of light color to darker shade.
10 segments.
Two last rows I turned the rug to wrong side up and crocheted 2 rows of sc.

On the wrong side - rubber compound SAF-T-BACK

The new one replaces the old one!