Repair Boulder Opal by re-shaping
A jeweler sent me this Boulder Opal which had been broken.
The best and really only way to repair a stone like this is to re-shape the broken side, keeping it as large as possible and contouring it in a way that makes it look like the stone was originally cut that way.
If the owner of the stone wants it cut into a different shape, then I do so. What ever the customer wants.