What are the origins of Quartz deposits? What other minerals, rock types and land formations are commonly found near quartz
There are multiple types of rock that you have represented there. I will say that the coloration of several (many) are likely due to dying rather than from natural processes, particularly the pinks and blues. They are not all quartz, although all but a couple contain what appears to be quartz or some variety of microcrystalline quartz (agate, chalcedony). The only one that I will declare as not quartz is the bottom-most one that is grayish black. That one is likely hematite. the ones with visible banding are examples of agate.
No idea... and from the picture alone I cannot even tell fi they are all quartz. The colour depends on its impurities anyways. All I know is that purple quartz is called amethyst. If you really need to know more about these someone needs to look at them in real life rather than just a picture. Hope this helps at least a little xx