Opal is a hydrated silica material with a hardness of 5.5 to 6.5. It is composed of submicroscopic silica spheres that are bonded together with water and additional silica. Some, but not all Opals exhibit the play of colors known as ‘fire.’ This is caused by the Opal’s minute silica spheres being packed in a formation regular enough to cause light diffraction. The name Opal is derived from the Latin opalus and the Sanskrit upala, meaning ‘precious stone.’
Common Opal may be any of several different colors, but it is generally opaque and does not show any of the ‘fire’ exhibited by precious Opal. Common Opal is found in many locations, but good white and brown/ black stones come from Oregon and the best Pink and Blue specimens are found in Peru. Common Opal vibrates at a lower frequency and gentler intensity than the transparent Opals and/ or fiery Opals, and this enhances its calming and soothing effects on the emotional body. Common Opal in all of its colors is a stone of gentle energies. It is well suited for sensitive people who are easily overwhelmed by more powerful stones, or for those who are overburdened with stress and need stones that will help them relax. Each color, of course, offers a somewhat different emphasis.
Pink Opal is a lovely stone for healing the emotions, especially those connected with subconsciously held pain. Opals are generally associated with past lives and the world of dreams, and these are the places from which old wounds can come to the surface. It is grounding for the emotional body and is an excellent stone to alleviate worry, chronic stress, and depression.
Simmons, Robert; Ahsian, Naisha. The Book of Stones, Revised Edition: Who They Are and What They Teach (several pages). North Atlantic Books. Kindle Edition.