Opal is a beautiful gemstone with an internal structure that makes it diffract light. It can display iridescent colour flashes when held at different angles. This optical occurrence is known as opalescence. The intensity and distribution of the color flashes is a determining factor in the value of an Opal. Opals can take on many colours depending on how it was formed.
Opal colours range from clear through white, grey, red, orange, yellow, green, blue, magenta, rose, pink, slate, olive, brown, and black. White and greens are the most common. Opal can vary from opaque to semi-transparent.
Opals are believed to be joyful and uplifting. It is said to bring true love to its wearer. Opal is the birthstone of October.