The word Synthetic is unfair; Synthetic Ruby is made from corundum the same as its 'Natural' sister. Made in the lab, in a controlled environment, they have become environmentally friendly and affordable Celtic knots in sterling silver jewelry represent eternity and unity in forces like Earth Wind and Fire We ship Silvershake Simulated Red Ruby Gemstone 925 Sterling Silver Celtic Knot Weave Solitaire Ring Jewelry July Birthstone in anti-tarnish protection, reinforced gift boxes with satin-style pouch with a guarantee period far-exceeding our competitors It is fitting that the Ruby belongs to the Summer month of July as its birthstone; it's also known as the 'Gem of the Sun' Silvershake Simulated Red Ruby Gemstone 925 Sterling Silver Celtic Knot Weave Solitaire Ring Jewelry July Birthstone Size 5