Opal body tone and brightness scale dark-opal Stunning Chinese writing in this

Stunning Chinese writing in this gem black opal

Bodytone is N2 and Brightness is B4

A top high gem black opal with a nice high dome and very bright colors

This high domed gem light opal is perfect for a ring setting

Opal body tone and brightness scale dark-opal Stunning Chinese writing in thisSick of trying to guess what the body tone and brightness of your opal is? Now you can accurately measure from a calibrated scale. This scale has been created with a durable plastic material and is compact to ensure you can take it anywhere. It will help you grade your opal with ease only to be used as a guide. The body tone(N) values have been measured by Anthony Smallwood the author of the official grading system used worldwide. The brightness is