Quartz Microstructures
(1) Isograds demarcate different regions where metamorphism occurred at the same temperature and pressure conditions and are useful in figuring out the tectonic history of a region. One very easy thing to add to the page would be a map with isograds plotted on it, or maybe just the etymology of the word "isograd." The stub does a decent job of explaining the basic concept, but does not explain it in-depth or give any real idea of application. There is no "visual communication."
(2) Shocked quartz is a quartz with a specific microstructure resulting from very high-P/moderate-T environments(read: high energy impacts) and is therefore a good marker of these sorts of events. It might be nice, though, to have a little more technical information about the formation of the microstructures on this page. The language is clear and I feel their explanations are good, however the section titled "Structure" doesn't really say anything about the structure. There are two pictures: the top one is pretty bad(blurry), but the bottom one is good.
- Sorry it will be late. I figure that's better than being half-assed, though.