My first truly disappointing run. Dull after 6 weeks.

Wow, that looks very familiar.  I had accumulated several large rocks that were too big for the vib.  It was getting to the point where my 12 lb Lortone barrel was getting kind of thin, so I got a new 12 pound barrel and ran the large rocks, some smaller ones and ceramic filler through 220, 500 and micro alumina.  I only ran for one week each but my rocks (including one piece of unakite) looked almost the same as yours as far as polish goes.   When I saw the lack of shine my first thought was that the 12 pound barrel is just too punishing on rocks (especially with larger rocks) to get a good shine.  But I am pretty sure I made a run all the way through when my original barrel was new and it turned out ok.  I think the water was about what I would normally do (to bottom of rocks on top).  Haven't figured it out but kind of decided that if it can't fit in the vib, it is going to go under the saw.  

It might be interesting to make a run with more water than normal to see if it cushions the rocks more.  
is your barrel a Lortone? 
The small stones in the background look polished.  Or were they wet?   

It looks to me like they need more time in coarse grind? I would say a month minimum. I'd add a pre-polish stage, and fill the barrel to 80% full with rock and media for polish and pre-polish stages.

It also looks like you have several hounded rocks that may be difficult to polish - they look similar to rocks I've hounded over time.

Very possible.

Newbie sees new and unfamiliar terminology and has to ask ... 

"hounded rocks" : is that referring to rocks you have found yourself and not purchased from a rock shop  ? 

You chose those because you were worried they would undercut, and they did. I call that a success! Granites, Schists and Gniess are just too much of an unknown to have consistent success. I have tumbled granites that came out amazing, and the exact same looking ones are a flop. As a general rule the dark spots are mica, and will undercut the worse. The reds, oranges and yellow are the feldspar and will polish, but have a cleavage plane so they took can undercut. The whites and greys are quartz and that is where the true magic happens! I think you did very well considering what you had to work with!

Agreed!  I tumble a lot of those igneous rocks.  It's okay to have them mixed with other things, but when one of them doesn't come out of polish nicely, which is often the case, almost all the other rocks with it also don't have a nice shine.  In other words, one piece of granite or basalt or the others you mentioned, can ruin the entire polish batch.   I've had even one small piece of granite thumbnail size ruin the whole batch when it didn't polish well.

As an exception to what I just wrote, often basic jaspers and agates do come out shiny in batches in which a lot of other things have gone wrong.  This amazes me when it happens.  Guess some of them are really tough. 

So the safest way is to have only one of them (I think of it as the experimental rock to watch) in a batch of rocks types that you know polish nicely.  It you get lucky, all come out great.  But with those types, it often doesn't, so you take that one culprit, but it aside and run it next in 1,000 grit to end up with a satiny finish as a keeper.  Oddly, doing that almost always results in a better surface than a polish run that failed.  

After than one culprit is separated, take the "good" ones back to 500 grit or 600 or 1,000 or whatever you use for prepolish, then rerun them in polish and they will come out great and shiny.

All that takes time, and some redoing of things, but it's been worth it to me to discover that one igneous rock that from time to time comes out of polish great.  Maybe only 10% of them do though.