What's in the other barrel?

As you can see, my tumbler has two barrels. The first barrel is currently running the rocks I've been documenting here on the blog in the fine grit stage, so what's the second barrel doing these days...Granite.

The near universal conclusion on the forum is that tumbling granite is usually not a good idea. Granite tends to be a bit on the soft side (although that can be compensated for) but the big problem with granite is that it is made of lots of flecks of different materials which are not always the same hardness or toughness. This means that when you tumble granite, it is really hard to get it smooth and round and to get it to take a polish. All that being said, granite is about the only remotely nice looking rock that seem to occur here naturally (meaning I can gather it for free) so I thought I'd give it a try anyway. Besides, it's like Strong Bad says, "when have I ever backed down from a bad idea." We'll see what happens.