Albite and quartz are also important constituents of the schists. Together they are more abundant than mica in the average schist on Mount Mansfield but because they are not so “showy” they are more easily overlooked. Both minerals are white and granular. Quartz, which consists of silica or SiO₂, is the principal constituent of most beach sands. In the typical mica schist, quartz is glassy in appearance and occurs as small rounded or irregular grains without plane surfaces. _Albite_ is a variety of plagioclase feldspar having the composition of NaAlSi₃O₈. It has a white chalky appearance and occurs in small equidimensional grains bounded by flat surfaces which break along plane surfaces that reflect light in certain positions. On the west side of Mount Mansfield some of the rocks contain so much albite and so little mica that the rock is granular in appearance. _Chlorite_, variety pennine, is an important mineral constituent of some of the schist. Chlorite is characterized by its green color and small amounts are responsible for giving a greenish cast to much of the schist. Like mica it occurs as thin sheets which reflect the folding of the schist. Garnet and magnetite are locally abundant minerals in the schist. _Garnet_ occurs as pink to red grains ranging from pin point to pea size. Most of the grains are rounded although a few occur as equidimensional crystals which have twelve equally developed faces. Garnet has a semitransparent, glassy appearance and is harder than a knife blade. _Magnetite_ occurs as bluish-black metallic masses with about the same size range as the garnet. Although most are rounded masses, crystal faces are developed on some. Perfectly developed crystals occur as _octahedrons_ which is the form consisting of eight faces, as two four-sided pyramids with their bases together. The larger grains of magnetite have sufficient magnetic power to attract or deflect a compass needle. The garnet and magnetite usually do not occur together, but each may form localized concentrations as lenses or layers in the schist. In smaller amounts, usually visible only with a hand lens or microscope, the schist also contains a green mineral called epidote, a white mineral apatite, and an elongated black mineral called tourmaline. Locally, as on the Nose Dive ski run above the Toll Road on Mount Mansfield, slender needles of tourmaline are visible in the schist.