Granite is a granular (coarse-grained) rock which has a glassy luster and is too hard to be scratched appreciably by steel. It may be white to gray, tan, brown, or pink to red in color, but pinkish to red granite predominates in Missouri. Some black stone, referred to locally as “black granite,” is usually a variety of gabbro. Most Missouri granite is coarse-grained, so that the constituent mineral grains—quartz, feldspar, and (less frequently) mica—can be readily recognized by anyone familiar with those minerals. It makes up many of the mountains and hills in Iron, Madison, and St. Francois counties and adjacent regions. North of the Missouri River, or where the glacial deposits remain, granite boulders may occur in the sandy and clayey glacial drift. The mineral quartz is recognized in granite by its glistening, oily luster, really more brilliant than the luster of glass, and by its curved to irregular broken surface. Furthermore, the brilliant luster of quartz is not dulled by exposure to weather. The mineral feldspar, in granite, has a glassy luster on the tiny flat cleavage faces where the individual grains are broken. Where weathered, feldspar becomes dulled, and chalky to dusty or clayey. Fresh feldspar may be glassy, white, buff, pink, red, in intermediate shades in color. With the mica, it imparts most of the color to granite. Mica is recognized by its softness and its ability to be split very easily into tiny flakes. Other minerals may be found in granite under the microscope, but they have little importance or significance. [Illustration: Granite at the “Elephant Rocks,” Graniteville. The large boulders now rounded by weathering are remnants of a higher part of the large granite body which underlies this region. (Photograph courtesy of Mr. Noel Hubbard).] Granite is an intrusive igneous rock; that is, it solidified from a hot liquid state (like lava) in a large body, beneath, or surrounded by pre-existing rocks. Because of slow solidification a coarse-grained texture was developed. In southeastern Missouri where granite is now exposed at the surface (for example, the Elephant Rocks State Park at Graniteville), that granite was covered originally by hundreds of feet of rock at the time it solidified from a liquid. During the millions of years which have elapsed since the granite solidified, its cover and the upper part of the granite have been eroded away by streams and rain after weathering to soil material. In fact, the ocean has covered the area several times during its long geological history.