The Cochise County Rock

Monthly Newsletter of the Sunsites Gem & Mineral Club

www.cochisecountyrock.org

“Finding and Grinding Rocks in Cochise County, Arizona since 1967”

October 2009

This issue edited by Don Hammer

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The next General Meeting of the Sunsites Gem & Mineral Club is on Monday October 12 at 7 pm at the Sunsites Community Center. Paul has invited Joe Hoscheidt, Discovery Days Coordinator, Mt. Lemmon SkyCenter to tell us about their programs but he has not confirmed yet. If not we’ll have another in the Renton Geology Series on DVD.

September 9, 2009 General Meeting Minutes

Paul McKnight called the meeting to order at 7:05.

1st item: Call for vote to approve minutes as published from June meeting. Approved.

2nd item: Treasurer's report. Walter Sigel reported no changes since June except for interest earned on the CD of $11.99 bringing the balance to $3,236.78.

3rd item: Field trips, reviewed by Henri van den Bos. July: W Mountain north of Willcox to see very well-preserved pictographs and many mortars (grinding holes) revealing well established early Indian habitation. August: French Joe Canyon in the Whetstone Mountains in search of coral and jasper.

September 19: Silver City, NM to look for Fluorite. The Club will meet at the Safeway in Willcox at 8:30 for departure at 8:45. High clearance vehicles are not necessary and car pooling is recommended.

4th item: Board proposal that the lapidary operation be moved from its present location at the Sunsites Fire Dept. facility to an available facility owned by the Fire Dept. in Richland. Larry Strout, who operates the lapidary program, and Larry Edgett, who is also a board member of the Fire Dept. explained the situation to those members present. Larry Strout outlined the advantage of the move as well as what would be involved in making the change. The Richland facility is 2 to 3 times larger than our present facility. However, it would be necessary to do some electrical and plumbing work by qualified members, if possible. Members would also need to help with moving equipment and setting up. Larry Edgett explained the position of the Fire Dept., the board of which has voted to take over the present facility in Sunsites for its own use. There is therefore no choice but to move the lapidary operation. In return, the Fire Dept. is

offering the Richland facility for $1 per year and would pay for the water and electricity. The Club's only expense would be to improve the facility for its use.

After some discussion, Paul made the motion to accept the offer of the Fire Dept.to make the move to Richland contingent upon determining costs for improvements within 60 days or sooner. The motion was seconded and approved by voice vote, Larry Edgett abstaining due to conflict of interest.

5th item: Announcements. The Club has been invited to man a table at the Saturday morning Farmers Market held at the golf course, selling baked goods and perhaps other items of interest. 15% of profits would go to the golf course and 85% to the Club. The motion was made to request the dates of Oct. 24th, 31st or Nov. 7th. to participate in the program. The motion was approved, Diane Dunn will organize the effort.

Diane Dunn and Zoe Schnabel provided refreshments for the evening. Paul made a sign up sheet available to provide refreshments starting in October through May.

Intermission was followed by the raffle and then viewing of the DVD "Sculpting of the Landscape" from the series THE NATURE OF EARTH by Professor John J. Renton of the University of West Virginia.

September Field Trip

Early on Saturday the 19th seven cars loaded with rockhounds departed from the Safeway parking lot in Willcox and headed east for New Mexico. After a pit stop at the Lordsburg rest area we headed north toward Silver City.

There is a town just south of Silver City called Tyrone where there are large mountainous tailing piles. Right before we got to the tailings we hung a left and headed west toward the Burrow Mountain area. After some minor confusion about which fork in the road to take, we ended up in the target area.

There was a vein of green and purple Fluorite running along a mountainous area for about a hundred yards. We parked at the north end of the vein and most of us concentrated our efforts right there.

Always the explorer, Bob Fenner walked toward the south end of the vein and came back with his panniers holding about 40 pounds of the stuff. Always the hard rock miner, Henri excavated some very large and colorful pieces.

The weather was perfect - mild and overcast. We found some beautiful rocks and a good time was had by all.

Ride Sharing

Anyone needing a ride or wanting to share for a Club event should attend the General Meeting and work out ride arrangements at the meeting.

October Field Trip

On Saturday October 17 meet at 8:30 am in the parking area near the intersection of Birch and Kansas Settlement Roads. We will be going back to the Three Sisters for garnets. Bring digging tools, light rock breaking tools, water, lunch, sun protection, bags or pails and lawn chairs.

Lapidary and Silversmith Classes

We are ready to resume lapidary, silver soldering, silver smithing and wire wrapping classes. Call Larry Strout at 826-3991 if you would like to attend lapidary or wire wrapping. Larry is also teaching silver soldering, a prerequisite to silver smithing. Keith McRobert will resume teaching silver smithing. Call Don Hammer at 384-3105. Come and join the fun of lapidary, silversmith, and wire wrap lessons. Interested, any questions?

Dues

Dues are due. Bring your dues to the next meeting or mail your check to Sunsites Gem & Mineral Club, PO Box 87, Pearce, Arizona 85625. Unpaid members were dropped from the Club roster on March 31.

Club Calendar:

October

12 General Meeting

17 Field Trip

29 Board Meeting

November

9 General meeting

14 Field Trip

December

3 Board Meeting

14 Christmas Party

30 Board Meeting

January 2010

11 General Meeting

23 Field Trip

28 Board Meeting

February

8 General Meeting

13 Field Trip

25 Board Meeting

March

8 General Meeting

13 Field Trip

April

1 Board Meeting

12 General Meeting

17 Field Trip

29 Board Meeting

May

10 General Meeting

15 Field Trip

27 Board Meeting

June

5 Club Picnic

Upcoming Regional Events

October 2009

10th–11th

Payson Rimstones Rock Club 12th Annual Gem & Mineral Show Mazatzal Hotel & Casino Event Center - Bingo Hall Tonto Apache Reservation

Admission: $3/Adults, Children under 12 Free

Discount Tickets Available @ Payson Chamber of Commerce, Payson Library, Parks & Recreation Office Barry Jones, 2009 Show Chair, 928-476-3513

10th–11th

Huachuca Gem, Mineral & Jewelry Show

At the Elks Lodge on Wilcox Avenue; Sierra Vista, Arizona Free admission and parking; live demonstrations, educational displays, rocks, jewelry, gems, minerals, fossils, equipment, lapidary supplies & more! 35th Annual Show presented by the Huachuca Mineral & Gem Club-proceeds benefit the club's scholarship fund. Contact Ingrid at 520-459-3718

Engineering and Mining Journal - June 5, 1897

THE PEARCE MINING DISCTRICT, ARIZONA

Written for the Engineering and Mining Journal by F. M. Endlich

Within the past year, Cochise County, Arizona has come to the front with a phenomenally rich mine, the Pearce. It is located on one of the outlying hills beyond the easterly slope of the Dragoon Mountains. While these latter show a core of metamorphic rocks, flanked by copper-bearing carboniferous limestones and traversed by intrusions of porpheritic character, the more or less isolated hills and ridge-shaped buttes to the eastward apparently belong to the trachitic and rhyiolitic series. The structure of the upper portions of these rocks is, to some extent, columnar, and, consequently, the hillsides are heavily covered with detritus and angular fragments of rock, the results of disintegration. At a number of points, however, in spite of this covering, quartz veins protrude above the debris, standing out prominently by virtue of their uniformly hard character and pronounced thickness.

At various places on the surface, as well as underground, these veins show a meandering or geodic structure, comparable to that of agates. This leads me to infer that these portions may owe their existence to secondary infiltration, and the comparative barrenness (so far as ore is concerned) of the silicious deposits as well as their separate inclusions of specific, metal-bearing minerals support this view. In strike as well as dip, the veins of the district show a certain similarity, the former being north of west, the latter ranging from 60 to 80 degrees to the southward.

Thus far the main development centers in the Pearce mine, located at Pearce Camp, a settlement of perhaps 800 souls. To the northeast, near Stockdale, is the Gold Cliff, and to the west of Fittsburg is the Six-Mile-Hill Groups. The first named was located March 10, 1895, worked in a desultory fashion by the Pearce brothers, subsequently bonded by Philadelphia capitalists, and on January 1, 1896, passed into their possession under the name of the Comonwealth Mining Company with a capitalization of $2,000,000. Active work was commenced under the management of John Brockman from New Mexico, who selected Mr. Towmey, from the same territory, as his superintendant. Shipments of ore were started about July, 1896.

The vein crops out for more than 3,000 ft., and exhibits the characteristics above noted. Three shafts are sinking, the deepest reaching 300 ft. They are served at present by horse whims, but connection between them is now being made, and the main shaft is being prepared for an inclined cage from Fraser and Chalmers. At an early stage of the mining work, it was found that the vein presented unusual dimensions, and it is claimed that the footwall has not yet been reached, although ore has been developed to a thickness exceeding 60 ft. A remarkable circumstance lies in the fact that nearly all of this material is of shipping grade. As an instance it may be stated that on the lower level, four gangs are working abreast (about 16 ft. front). The ore is hoisted directly into storage bins, without any kind of sorting, loaded into wagons, and started on its way to smelting works at Pueblo, Colo. Whoever is familiar with the costs of teaming, railroad freight for about 750 miles, and treatment charges on dry ores can readily understand that the ore must carry appreciable values.

The rich chute from which this ore comes has now been exploited for a horizontal distance of 390 ft. on the vein, for a depth of about 300 feet, and for an undetermined thickness ranging from 16 to upward of 60 ft. From the surface down no sorting has been done, nor are any waste-dumps in sight. The lower grades of ore, which form an inconsiderable minority, are reserved for treatment in a mill now building. For the past six months the shipments show a monthly average of about 2,000 tons. Many guesses have been made as to the value of this ore, but they are not reliable. From the best information obtainable, I should place the monthly output as upward of $250,000.

The ore itself is quartzitic, somewhat ferruginized. It carries both gold and silver, the latter in the form of chloride (cerargyrite), bromide (bromyrite), chlorobromide (embolite), sulphide (argentite), and some iodide (iodyrite). Gold occurs native in broad splotches and leaf form, and I suspect the presence of decomposed tellurides. In the upper levels the proportion of silver to gold was about 2½ to 1, but in the lowest workings it has gradually changed to about 1:1. Apparently the highest values follow the hanging wall, where streaks, veinlets, and inclusions, assaying heavily in silver, have been encountered. These occurances I am inclined to connect with secondary infiltration. Remarkable fine crystals of the above-named specific silver minerals are found, and in one instance a druze lined with wulfenite, encrusted with embolite, was struck.

The company has proceeded cautiously and thoroughly explored its ground before deciding upon reduction works. At present a mill is building which will have 40 tons daily capacity, capable of ready expansion to 80 tons and comprising the following appliances: the ore is first crushed in a pulverizer, thence passes to amalgamating pans, from these to settlers and receives final treatment on FRUE vanning machines. The tailings later on may or may not be subjected to some leaching process. The power is steam. Water is scarce, and the company is sinking a well of large dimensions to obtain an adequate supply. At present, there are 84 men on the pay roll, of which, however, only about one-third are employed underground.

From present developments it would seem that the chutes within the veins were, in this district, of unusual dimension proportionate, probably, to the thickness of the vein. It remains to be seen whether, in turn, they will be correspondingly separated from each other as to horizontal distances. This is an important question for those who are working smaller veins, but the chances are that the size of the rich chutes and the spaces of low grade or barren ground separating them will bear some definite relation to the persistency and transverse measurement of the vein containing them.

At the Gold Cliff mines not sufficient work has been done to develop a paying chute, but the mine is now being properly opened at a depth of 75 ft. A company of Los Angeles and Tombstone men, with George H Fitts, of the latter place, as president, has acquired this property and is working it in a judicious manner.

The Six-Mile-Hill Group is largely owned by Mr. Fitts. A depth of 70 ft. has been obtained in the workings, and several [missing text] have been encountered. Further development will [missing text] establishment of a pay chute, as both here and at Gold Cliffs [missing text] features and surrounding of the veins are closely [missing text] Pearce.

Taking it altogether, the district is one of exceptionally [missing text] from its metallic wealth. The proximity of the Dragoon Mountains with its copper mines, the absence of copper at Pearce, and the sudden appearance of high grade silver ores, form a combination that leaves ample room for speculation upon the distribution of varying mineral compounds in large quantities within a circumscribed area.

Club Officers for 2009

President: Paul McKnight 520-824-4054

V.President:Henri van den Bos 520 384-0288

Secretary: Jim Brower 520 826-4672

Treasurer: Walter Sigel 520-826-1009

Delegate at Large: Larry Strout 520-826-3991

Hospitality Coord: Zoe Schnabel 520-826-0100

Past President: Don Hammer 520 384-3105