Hmmmm. Don't know how much help I can be, but since one of my poor attempts at humour was quoted, I'll try.
Will start with the "high-grade" price. From what I've seen the real top-grade rough can and does reach into five figures per ounce. I've gotten parcels with what the average person (including me) would call high-grade for well under $1000/oz. As the price goes down, the color bars get thinner or wavier or have more inclusions or other problems. But you can still cut very nice opals from between the problem areas.
The type of opal (black, white, crystal,...) and source (LR, CP, Mintabie,...) will have major influence on price too, so there's really no way to guesstimate price per ounce for rough without considering those factors.
Given my experience over the past two years, I'd recommend that any new cutters try to visit a gem show where rough opal will be sold, to see some different grades first-hand. Then do a lot of comparison shopping.
And then there's the "rule of thirds" that's been quoted several times around the forums, where you can expect to lose money on 1/3 of parcels you buy, maybe break even on 1/3, and make a profit on 1/3. Of course there's no guarantee that if you buy three parcels you'll get one of each. How's that for an "encouraging word"...?
Just work your way up through the price ranges you feel comfortable with. The practice you get on cutting lower grades will be well-appreciated when you hit a problem in a higher-priced piece.
