Arizona republican., 1909-02-25

of contact of an eruptive rock with limestone and may be regarded as the result of contact metamorphism. It also occurs in reefs traversing limestone, like veins of quartz, at some distance from a contact plane, in origin, seemingly the result of siliceouS emanations.
 Small but dark-red garnets occur abundantly in the gravels and sands of the streams descending from the Catalina mountains north of Tucson in association with heavy black sand.
 Garnet, when derived from the pure limestone of the Modoc formation, forms large masses 50 to 100 feet thick. as on the western slope of Modoc Point at Morenci. and on top of Shannon Mountain at Metcalf. Gindgren)
 Pyrope garnets of fine deep color are obtained in considerable quantity from the Navajo Indians of North eastern Arizona. The report on the production of precious stones in the year 1907 published by the United States Geological Survey, says: "A quantity of pyrope garnets was col lected from the Indian reservation in Northeastern Arizona and Northwest ern New Mexico. MT. J. l.. Hubbell of Ganado, Arizona, mentions a To- cality about seventy-five miles west of north of Ganado where garnet is found abundantly over a stretch of country about ten miles long. The garnets are picked up from the sur face of the ground by the Indians" They occur in sandy soil. and are uncovered by the action of the wind.
 The largest of these garnets are transparent and suitable for cutting. They make valuable gems. A black garnet in good rhombic dodecahedrons is reported by Geo. P. Hunstock, 1905. at Superior, and red garnets of similar specialization from the Graham mountains by Col. Benj. M Crawford. See also Grossularite).
 GLAUBERITE.
 Sul phate of soda and lime. Sul- phurio acid 576, lime POI, soda 22.3.
 At the Thenardite and mirabilite beds in the Verde valley, in thin tabular crystals, often changed to calcite.
 GERHARDlTE.
 Basic copper nitrate, Nitric acid 225 cupric oxide 66.2. water 11.3.
 Avery rare mineral first identi- fled from Arizona by Messrs. Wells and Penfield at the laboratory of the Sheffield Scientific School, among some ores sent to the school by Mir. Thomas from Jerome Careful search at the locality has since failed to reveal its presence there. And it was sought in vain at the copper mines. until Lindgren and Hillebrand re- ported finding it in green coatings on the cliffs of porphyry in the deeply eroded Chase Creek canyon at Metcalf. It there appears to be formed by the trickling of atmors- pheric waters over and through rocks a small percentage of cop per. It is locally known as green paint" and is not soluble in water, but chemical examination showed that the copper minerals consist of a nitrate and a chloride. The au- thors in conclusion state that the l mixture contains, presumably. the ba- sic nitrate, Gerhardite, and a chloride. | which is perhaps atacamite. (Am. l Jour Sci, Dec. 1904)
 GOLD.
 Gro, Gro nativo, rarely pure; gen. orally alloyed with silver. California | gold is mostly ST to S9 per cent fine. ! The purest known gold is from Mt | Morgan, Queensland, yielding 99.7 to 99.S of gold.
 In Arizona nearly every mountain | range has one or more gold mines or. at least, gold-bearing veins or de-. posits.
 Of all metals gold is the most | widely and generally distributed in | all parts of Arizona. It occurs either as placer deposits or in veins, or in with copper ores. from Yuma on the west to the New Mexi- can line on the east.
 It is not possible. to do more in this list than to name some of the more important localities which have been explored and developed
 The Fortuna mine near Yuma has been a large producer of the metal.
 North of Yuma, along the Colorado especially, there are several localities where coarse gold has been found in copper ore, notably at the Ellen Iowan claim and in the region of La Paz.
 Desert gold mines 21z miles north ,f Vicksburg, Yuma county, in veins md in placer deposits (dry washing)
 The King of Arizona has been, and s still. large producer.
 Mack's mine, a few miles north of Parker, wire gold in copper ore.
 The Congress mine, in Martinez mining district, Yavapai, is well known for its large production, and 'or the depth and extent of the The gold is closely asso- dated with pyrite.
 Rich Hill, not far east of Congress, s celebrated for the number, size md great aggregate value of the nuggets found there and for the ,oarse gold in the quartz vein.
 Vulture mine, coarse gold in brill ant sheets was often found, asso- dated with galena and wulfenite, arosite and pyrite.
 Southern Belle mine, Old Hat dis rict, Santa Catalinas; Mammoth and mines, Shultz, Pinal county; Saddle Mountain district, at Pools mines; Ash Creek Gold Co.
 Tombstone mines, especially at the associated with horn sil- Ter and lead carbonate.
 In quartz, crystal lode, Big Bug. Iavapai In quartz veins on Cherry reek, Yavapai. which adjoins the copper ore.
 |.