The celtic knot is an ancient symbol of the journey of life. With no beginning and no end, the knot represents the timeless nature of our spirits and the world we live in. A Ruby celtic knot combines these concepts with the spiritual attributes of the Ruby . Ruby is known as the gem of courage. Wearing a ruby pendant can help you get through the trials and tribulations of life. Tanzanite is the gem of fortune and luck. A tanzanite pendant is said to ease stress and free one from bad habits.