These gems have been assessed, cut and roughly shaped, in preparation for a final polish.  They may be further shaped or left, as is.  All of these are high quality pieces, that carry no sand or inclusions and are ready for the new owners final touches. It is incredibly satisfying to create such beautiful gems yourself.  

This avenue takes the guess work out and knowledge required to assess and rub back rough opal, to expose colour and the gem inside.  It is very easy to misjudge this process and render the rough less valuable.  All the risks are taken by the cutter, to produce something, the new owner can be sure to produce and profit from, once finished.

This of course relies on the individual skillset of the cutter and the machines available to them, to finalise this process.  So results may vary.  There are a vast array of resources across the internet, as to how to final polish rubbed gem opals. Normally a small amount of weight is lost to this final process. These cannot be returned, if the new owner affects or interacts with the gem. All pieces and exact weights are documented, for this reason. 

There is the prospect of gaining value, by polishing yourself, to realise profit.  These are cheaper than finished stones, so represent a great opportunity.