Celtic button knot

A Celtic button knot is a stopper knot on a single rope that results in a spherical decorative knot with hair braid / basket weave pattern. It is essentially a single strand Turk's Head Knot that is structured such a way that it is effectively tied around the rope itself, creating a stopper. It typically is used as a button, or as a knot securing the end of the rope from fraying.

Tying
There are 4 main steps to tying the Celtic knot:
 * 1)  two consecutive overhand loops, the last one placed partially over the first forming two petals of a four petal flower
 * 2)  left end woven from right horizontally through the loops; over, under, over, under forming the third petal
 * 3)  left end woven again from left: over the edge, under, under, over and up through the central hole finishing the four petal flower
 * 4)  optional: pushing the end again into the knot following the main part consistently on the inside. This may be repeated to give volume to the knot
 * 5) tightening evenly to close the petals of the flower forming a sphere around the main part