G day Hare-Twigga
Sample 1, Txet Book Granite I would say, the round glass grains are in fact quartz, the yellow would be pyrite, as when it fresh spilt it is yellow in colour, the cubic scares I would take a guess and say were left by Platinum, if you know the spot might be worth expanding your knowledge base on platinum, worth in the ball park of Au, Platinum in its life cycle is known to whether from igneous rock, it gathers into grains and then forms nuggets and placer deposits. So another area you may wish to invest some time in.
Sample 2, fine sample, text book dolerite, The small rectangles etc are from Plagioclase crystals.
Sample 3, the conclusions on limonite I'n not convinced, maybe the orangey brown part, but I ve never heard of limonite in red, or Fe2 influenced. Again any real conclusion would require some basic field testing, but what I think you have here is just a chunk of sedimentary stone, comprising mainly sandstone with some minor layers, of I don't know what, hard to tell from the photo.
Of course I could be wrong, I guessing from photos, so no shooting if I am.
If you ever want to take a look at these area's I'd love to get your opinion on them. Go you halves in the Platinum Deposit! 
