Prof. A. A. Julien, in a communication to the New York Microscopical Society, in January, 1892, announced the discovery of the wellpreserved mycelium of a fungus, secreting iron oxide in the jasperized wood from Arizona. To which he attributes the coloration of the agate as detailed in the last report of this series.
Agatized wood in large quantities, consisting of trees from 12 to 35 feet in length and from 18 inches to 2 feet in diameter, has been found near Calistoga, in Napa county, California. True examples of agatized and opalized wood and bluish chalcedony associated with quartz are found in the vicinity of Gallatin, Montana, great quantities of which were collected by Dr. Albert 0. Peale and Prof. George P. Merrill, and later by Prof. Frank H. Knowlton, of the United States Geological Survey, for the United States National Museum.
OPAL.
Opal was not observed as a precious stone in the United States until 1889. Since then it has been found in gems equal to the Hungarian in Washington State, Idaho, and Oregon.
In August of 1890 a flue opal was detected in digging a well near Whelan, 20 miles southwest of Colfax, in Washington State. This was in latitude 47 degrees north and longitude 117 degrees west, about midway between the Coeur D'Alene and the Nez Perce Indian reservations, near Moscow, Idaho, almost on the line between Idaho and Washington. It occurred more or less plentifully, aud the last 4 feet of the rock contained cavities filled with precious opal. This opal occurs in a basalt, in which most if not all of the feldspar and pyroxene as well as the green mass appears to be altered. Buildings have been erected and the locality named Gem City. The total yield of these mines, during the summer and fall of 1891, amounted to over $5,000; the opal is fine, in many respects equal to the best material from the Hungarian or Australian mines. A gem weighing 3J carats from this district was held at the extravagant figure of $500, partly perhaps on account of its American origin, and a rough mass of 2 ounces at $1,200. If the material is as abundant as supposed, and is properly worked, it is likely to be one of the most promising of our precious stones from a financial point of view, notwithstanding the abundance of fine stones now being found in Queensland and more recently at Wilcanuia, New South Wales.
Some remarkable fine fire opals have been found 30 miles from Hepner, Morrow county, Oregon. At this place, immediately overlying a bed of hardened or baked clay or silicified slate, there is a deposit of eruptive ashes about 4 feet in thickness. This, in turn, is overlaid by ' red lava and other lavas to the top of the mountain. In this bed of ashes are found large nodules or spherical masses from 1 to 40 per cubic yard. These vary in size from one to several feet. On breaking them open, they are found to obtain some kind of opal, of which one in twenty is a fire opal or a noble opal. It is estimated that some $20,000 worth of specimens have been obtained here during 1892; many of these were stolen at the Spokane fair so that the estimate may be exaggerated.
