Contraluz - (the contraluz effect occurs when the light is inserted inside or laterally) - pieces with contraluz effect are rare Natural opal rough Crystal Contraluz Ethiopian Welo Untreated! Beautiful Color Multicolor flash fire 1 piece (28x21x18 mm) about 11 grams - 55 cts Photo with lamp light condition! beautiful colors also sunlight! Wet Piece - Photo wet piece Keep moist Opal acts as a prism within the aura, bringing a full spectrum of Light energy to the system, soothing and clearing the emotional body, and boosting the will to live and the joy of one's earthly existence. It is believed that certain gemstones and minerals have beneficial health and spiritual properties. Catawiki cannot guarantee or be held liable for these suggested attributes which have no scientific evidence. Standard shipping ( 2-7 days for Italy ) ( 10-20 days for Europe ) ( 15-45 days for rest of the world )