We found a few specimens like this, where you could see small green crystals in the rock with close inspection or magnification. In the photo, this looks a lot like the aventurine (green quartz) that you can find at the mine, but the crystals and color are more like emerald. The stones used in the driveway are a mix of blue and green and red from all the different rocks and minerals... jasper, agate, quartz, corundum, beryl... beautiful.
Green Gem
From Anne Marie Helmenstine, Ph.D., About.com
Many of the minerals at the mine can be green, but three are more common than the others. There is aventurine, which is a green quartz. There is hiddenite, which tends to be brighter and lighter green than most emeralds, and then are emeralds.
Anne Helmenstine©2009 About.com, a part of The New York Times Company.
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