Opal is the national gemstone of Australia where it is in abundant supply. Opals are commonly found on other rocks, such as sandstone, rhyolite and basalt, giving it a matrix of varying color.
From the word opal we derive the term “opalescence” which is used to describe the milky and shimmering reflection we see within the more commonly found white opals. This term is not used to describe the “play of color” we see in colored opals. This color play is caused by the process known as diffraction where waves of light cause the diffusion of color within the crystal. Some opals may carry the full color spectrum and others more limited concentrations of white, yellow, orange, green, brown, black and blue. Fire Opals, red against black, are the most rare.
The luminous color found in Fire Opals renders its own combustible metaphysical properties. Red opals are great activators for the chakras and motivators for action. They help to initiate new ideas and stimulate enthusiasm. It is said they stimulate sexual energy and the adrenal glands. Even if you do not possess a Fire Opalone, viewing the powerful and colorful interplay of the image above is quite activating and speaks of optimism. (See also Fire Agates.)