Another magnificent opal is described by Jackson as having been exhibited at Vienna. It was nearly an inch in length, and was of the harlequin order, having three longitudinal bands from which flashed resplendent flames of light and color. It was pronounced by the virtuosi of Dresden and Vienna to be the third in rank of all the fine opals then known. In the Musée de Minéralogie of Paris may be seen a splendid opal which has been carved into a bust of Louis XIII. when a child. King very properly exclaims against the barbarism and extravagance where work and material mutually destroy each other’s beauty and value. The Spanish historians, in their marvellous stories of the wonders seen in Mexico at the time of the Conquest, describe the image of the mystic deity Quetzalcoatl (God of the air) on the great pyramid of Cholula, as wearing a mitre waving with plumes of fire, and which was supposed to have been produced by masses of the fire opal. Dr. Le Conte brought home from his geological surveys in Honduras, a number of beautiful opals from the mines in that country. They have since been cut and mounted in gold with diamond settings, in the form of a necklace, which is regarded by connoisseurs as one of the most valuable jewels in the United States. At the Centennial Exhibition of the United States, Austria exhibited some very beautiful opals of various kinds, both polished and in the natural state. One of the polished gems was two inches in diameter and valued at $25,000. It was of a faint milky white tint, like most of the Hungarian opals, and displayed a charming arrangement of colors. The splendors of the opal are best seen when exposed to the direct rays of the sun, and viewed through a magnifying glass of low power. The dazzling scene has no equal in art or nature, for the vivid hues of the solar spectrum are here displayed with the most charming effect. The colors are in broad patches and not blended with their complementary hues as seen in the continuous spectrum, and the effects of the pure green, red, blue, and yellow, flashing forth in perfect purity and intensity, without definite arrangement, remind the observer of the brilliancy of the kaleidoscope. In this fascinating display of hues one might expect to see the colors pass into each other as in the solar spectrum, and as the field of view is changed; but such is not always the result. The red may exhibit a tinge of yellow, or the green a shade of blue before they disappear from view; but generally the patch of color ends abruptly, preserving its purity of tint to the last.