This absolutely stunning top gem Semi-Black Opal is quite a piece. It weighs a very large 50.7ct and measures 50.5 x 20.5 x 8.1mm. The body tone of this opal is a semi-black crystal. The fire is very good. There is a blueish green rolling flash across the top. Just below that is a very beautiful bright green and blue pinfire and flashfire pattern. Below that is a red, orange, yellow pinfire sitting on the semi-black base. This stone is a true gem, which does not come around often. Do not miss out on the opportunity to own an opal like this.