Precious Gem stones production in 1911 Page 96



	GEMS AND PRECIOUS STONES.	1069

	turquoise lead, so that without the aid of a guide it was difficult to determine at what places turquoise had been found. About a dozen shafts and a large number of prospect pits and cuts had been made over a belt of country about 250 feet wide. Some of the shafts were 40 to 50 feet deep and around them were open cuts. At one of these a track for a mine car had been laid through the cut to a platform over the shaft to expedite the removal of rock. The turquoise is associated with decomposed rock quite similar in appearance to that on Mount Chalchihuitl. The rock is porous white to gray, and part is stained with iron oxides. Less altered phases are gray or drab, and some that has suffered little weathering is dark speckled gray. The tur- q uoise occurs in seams, veinlets, and segregations, as in the other deposits of this region. Some good pure blue gem has been found as well as considerable good matrix associated with brown limonite iron stains. Turquoise has been worked intermittently at this mine during the last few years, but little w.as done in 1911. Oxidized copper ores were found in the workings of the north end of the O'Neil mine. At A. B. Renehan's claim several pits, shafts, and open cuts had been made. Some of these were in part ancient workings. The latest work consists of an open cut about 75 feet long, 3 feet to 25 feet deep, and 6 feet wide. The rock formation is quite similar to that around Mount Chalchihuitl. The badly decomposed rock is nearly white and porous and less altered phases are bluish-gray. Turquoise is found in seams and veinlets in the decomposed rock. Some very good blue turquoise is reported to have been found. The claim was worked in a small way during 1911, but no turquoise was sold. Turquoise Hill is a low elbow-shaped ridge rising from 100 to 300 feet above the plains northeast of the Cerrillos Hills. It has four summits—a main summit and others, about 250 yards S. 25° E., about 300 yards west, and about 500 yards S. 75° W., respectively. The elevation of the main hill is about 6,400 feet above sea level. The hills are well rounded and slope gradually into the plains. Rock outcrops are not prominent, but the surface is covered with angular blocks and small fragments of rock, among which vegetation has a slight foothold. Like the plains, the hills are covered with only a light crop of desert grass, a little sagebrush, cactus, and a few scattered pine trees of stunted growth. The nearest water is Alamo Creek, about 2 miles north of Turquoise Hill, and water for camp use is hauled from Bonanza along this creek. The principal turquoise deposits have been found in the three lower hills, but a little turquoise has been found on the northeast side of the main hill near the bottom. There were rather extensive ancient workings over the best deposits and in some places the greater part of the turquoise had been removed. The famous mine of the American Turquoise Co., often called the "Tiffany mine" though not owned by Tiffany & Co., is located in the southeast hill. Other claims have been located around this mine, but the quantity of turquoise found has been limited. The old Castilian mine is located on the westernmost hill, and around it numerous claims have been located, accompanied by rather extensive prospecting. The openings on the third hill, lying north of east of this, are small and may be considered a part of those surrounding the Castilian mine. The American Turquoise Co. has six claims including those composing the Tiffany mine and part of the Castilian mine.