Common chalcedony has a waxy luster and is usually translucent rather than transparent. The transparent forms are known as “oriental,” the translucent as “occidental” chalcedony. Common chalcedony has little color, shades of gray and blue being the most common, although other tints occur. It usually presents rounded surfaces which have grape-like, kidney-like or stalactitic forms. It occurs coating other rocks or minerals or lines cavities or fills veins and clefts. It is never, so far as we know, deposited in any other way than by percolating waters. At Tampa Bay, Florida, the waters containing chalcedony have penetrated corals and preserved them, often giving forms showing the shape of the coral outside and a cavity within. Throughout the “Bad Lands” of the West, clefts in the hills are often filled with sheets of chalcedony varying in thickness from that of thin paper to nearly an inch. These chalcedony veins ramify in all directions and often extend for many rods without interruption. When the chalcedony is penetrated by branching forms of manganese or iron oxide the forms known as “mocha stones” and “moss agates” are produced. These are not due to vegetation any more than the similar forms of frost on our window panes. They are purely mineral in their origin. Moss agates are found in numerous localities in the States of Utah, Wyoming, Colorado and Montana. In the opinion of Mr. George F. Kunz “no stone that is used in jewelry in the United States is cheaper, more beautiful or more plentiful than the moss agate.” The best occur as rolled pebbles in the beds of streams. The name, “Mocha stone,” sometimes applied to moss agates is either due to the fact that those first used came from Mocha in Arabia, or it is a corruption of the word moss agate. The finest moss agates now known come from India. A white variety of chalcedony containing minute blood red spots is known as St. Stephen’s stone. Chalcedony was formerly used much more and more highly prized than at the present time. It was especially employed for seals and rings, but also for plates, cups and vases. These were often engraved in the most elaborate manner, the hardness and toughness of the stone making it well adapted for this purpose. The sentiment of the stone is: “A disperser of melancholy.” The name chalcedony is from Chalcedon, a city in Asia Minor, where the original chalcedony was found. This mineral was probably not like our modern chalcedony, however, being more probably a green quartz. This chalcedony is mentioned as one of the foundation stones of the Holy City in the Book of Revelations. [Illustration: QUARTZ (obscurely crystalline.) LOANED BY FOOTE MINERAL CO.] Left column: Bloodstone, polished (India.) Tiger Eye, polished (South Africa.) Center: Chrysoprase, polished (Arizona.) Agate and Carnelian, polished (Lake Superior.) Right column: Jasper (Germany.) Ribbon Jasper, polished (Siberia.)