Even after 30 years of being in the business, I still get sand sucker-punched by opal.
Just when you think you know your stuff an opal comes along to promptly remind you that you don’t.
Like an over-eager first-grader shouting “Ten!” when asked “How many fingers am I holding up?” only to be smugly reminded by the schoolyard bully that you, in fact, have eight fingers and two thumbs.
Cutters often ask of their nobby’s, “you’re a good opal, aren’t you?” to which the opal replies “Yes! No! Sike! I’ll never tell!” before sliding on some black sunglasses and pretending they don’t hear you.
Unfortunately in life, sometimes you’ve gotta find out the hard way.
I’ve picked out one of the nobby’s I’ve had my eye on and grabbed my brand new opal x-ray gadget (it’s a torch but I like to sound dramatic).
I always study the opal before I cut it to see how clean the color bar is.
You do this by shining a torch (aka flashlight) through the stone; if you can see the light out of the other side there’s a pretty good chance it’s clean. If you can’t, the opal either goes black inside or has been eaten away by sand inclusions. Two opposite ends of an opal cutter’s emotional spectrum.
I always start cutting at the edge of the opal first. This helps me to see where the sand might be running and get a better idea of how to shape the stone.
It’s looking like the sand will kill the whole thing so far which actually happens quite a bit with opal. Nonetheless, I grind down a little more just to make sure.
Unfortunately, I’ve been sucker-punched by sand inclusions and I have to reassess my approach. I’m going to cut a much smaller stone from the clear portion of the opal.
I pre-form the opal to get a nice shape before gluing it onto the dop stick with wax. Using cerium oxide and a felt wheel, I polish the face of the opal.
I usually smooth the back of the opal by hand but another way is to smooth using the dop stick. Glue the polished face of the opal to the dop stick with the wax as evenly as possible. A pitfall to this method is that you can’t look at the whole stone to see if it’s lopsided.
Smooth the backside of the opal and then the setting edge. Take the opal off the dop stick to see if it’s even; if it’s not, take it back to the wheel. This method also leaves some wax on the face of the opal. To remove this, use methylated spirits and rub with a clean cloth.
The big reveal…
Or should that be the little reveal? I was expected up to 15 carats from this big opal nobby but, due to the sand sucker-punch, I’m left with a smaller 3.10ct dark opal. This is still a great gem; sometimes opal won’t even give me that! It has a brightness of B3, is an N5, green-blue color and a high dome.
To all the budding opal cutters out there: sometimes you end up with a little, sometimes a lot, and quite a few times you’ll end up with nothing at all.
They are unique gemstones that always present a challenge. This is all part of the thrill of playing with opal.