This is a lovely Black Opal with Blue flashes across it.
8.7 x 6.9 x 3.1 mm at its widest points
Click image for larger version. 

Name:	bo1.jpg 
Views:	24 
Size:	28.3 KB 
ID:	9129Click image for larger version. 

Name:	bo2.jpg 
Views:	23 
Size:	27.1 KB 
ID:	9130Click image for larger version. 

Name:	bo3.jpg 
Views:	21 
Size:	27.2 KB 
ID:	9131