I would send it into ARA... They will refine it for you, and send it back minus 2%, which is not much at all... It would be in BB form though, but then it would be much easier to melt and mold into an ingot, etc...
I use borax .to shield to gold . google different methods . to much to sit here and type ...... look in gold prospecting section ,I do have some old post on this topic that will help . I believe it's under rock salt nugget .
To get the BB style, you have to pour the molten gold at a higher distance from the water pot and do it slooooowly and in small amounts. That gives the gold time to "pull" into a ball before it hits the water. It's the same technique used years ago to make lead buckshot.