Golden and Silver Beaches, on the east shore of South Bay, Raquette Lake, NY (central Adirondacks) are named, respectively, for the dark yellowish-orange (10 YR 6/6) and very light gray (N8) color of their sands. Only a small, 350 m wide peninsula separates the two beaches yet their hydrologic recharge areas are strikingly different. Behind most of Golden Beach is a typical upland area underlain by glacial tills whereas the area behind Silver Beach is a low-lying bog.

Sand from both beaches comprises >96% quartz, with the remaining 2-3% K-feldspar and accessories of red garnet, ilmenite, hornblende. There are two main differences in beach sand, however. First, all of the K-feldspars at Golden Beach are pink or reddish-pink colored due to the typical presence of microscopic earthy hematite inclusions along fractures and cleavages. However, K-feldspar at Silver Beach is largely pure white. The K-feldspar at both beaches is microperthite. Secondly, about half the sand grains (quartz & K-feldspar) at Golden Beach are coated in a pale-orange colored material thought to be either amorphous iron hydroxide or goethite. None of the sand grains at Silver Beach have this coating; all are clear or gray (quartz) and pure or nearly pure white (K-feldspar).

The very light gray color of Silver Beach sand is interpreted to be the result of extensive dissolution of amorphous Fe-hydroxide, goethite, and earthy hematite. Lakeward moving water from the recharge area behind Silver Beach is interpreted to have low pH and low dissolved oxygen, thereby enhancing the solubility of amorphous Fe-hydroxide, goethite, and earthy hematite. Sand grains on Golden Beach do not experience these conditions, and thus retain their typical Adirondack coatings of iron-hydroxides.