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San Diego Mine, Tombstone Arizona

Last Updated: 17th Dec 2016

By Rolf Luetcke

San Diego Mine, Tombstone Arizona
by Rolf Luetcke

Back in the 1970's I was exploring the dirt roads around Tombstone to find old mines with minerals I could use for the sample collection I was making at the time. Tombstone had a lot of small mines in the surrounding hills. The mines close to town were not open to collecting and most of those had signs to keep out or were fenced off. I had been driving to Tombstone on highway 80 from the East when I spotted a small dirt road to the South. This small road was 1 and 1/2 miles from town. I also saw there were mine dumps not far from the main road.
I drove up the small dirt road and at the first mine by the dirt road I stopped and got out to explore. The first thing I saw was that the rock on the dumps of the small mine had the manganese dendrites that looked like little plant fossils. I could use these in the collections I was making so found it a good place to collect since it was close to the road and easy to bring things to the car. At the time these dendrites were assumed to be pyrolusite but later analyses showed them to rarely be this mineral but mostly a mixture and since then called manganese oxides and manganese dendrites. Not much other than black manganese minerals besides the dendrites on the dumps so I collected a little and moved on a bit up the road.
A few hundred yards up the road and another road turned off to the East and a small mine was visible. I took the road to the mine and found a lot of material on the dumps. More of the manganese ores but also other things. I collected at this mine and took a selection of material to study at home and identify which minerals were to be found here.
When I got home I worked to identify which mines I had visited. The literature at the time was books and was sparse on which mines were which. The conclusion I came to at the time was that the small mines to the East of Tombstone were called the Tombstone Extension Mines. They were a small group of mines that didn't pan out into good ore bodies and never were very large. The statistics for the small group of the Tombstone Extension Mines is listed for 1 and 1/2 miles SE of Tombstone and contains three small, named mines, the Carper mine, La Grande Mine and San Diego Mine. The Tombstone Extension mines listed on mindat is where the symbol is for the first small mine up the dirt road called East Smith Ranch Trail. It is on the West side of the road as you go in from highway 80. The list shows the first mine across from the Extension mines as the Carper mine and this one we never could find. The next mine is the La Grande Mine and it is there and quite small and has similar minerals. The La Grande is not visible from the main dirt road but can easily be seen from the San Diego Mine. The San Diego Mine is actually the largest of the small group and is the one we stopped at most.
The group was mined for lead, silver, gold, copper and vanadium. Only about 40,000 tons were mined from all of this group between 1930 and 1954. The mines went about 168 meters deep and had a number of levels and over a thousand feet of tunnels. The statistics are listed for the whole group. The San Diego Mine had a small smelting operation that has a lot of black slag at the N. end of the mine dumps. This slag had pockets of crystals that I collected and later identified as augite, which formed while the slag was cooling. The augite did form some interesting crystals and under high magnification showed a bit of secondary spots of mineralization.
The San Diego Mine had a shaft that went down 122 meters and had 4 levels. There was a barbed wire fence around the main shaft since it was open and could be dangerous if walking or driving a vehicle without looking. The dumps here are the largest of the group. The group lists 21 different things found there and the San Diego 8. At the Tombstone Extension Mines is one wooden collared shaft with an old ladder that is open but looked too dangerous to attempt to enter. There was also a small, shallow trench that was lined in plastic that seemed to me to be one of two things. First thought here was a water retention spot since the area here is very dry water was needed. The second was a small leaching operation to extract gold from the dump rock. No records are to be found for this operation. Since the San Diego did have the small smelting operation the leaching was a strong possibility.
I walked to just about all the small dumps in the area and as I had noted, the listed Carper Mine I never did find. The La Grande Mine on mindat has a ? over the mine and it is there. I think the ? should be at the Carper since I never saw any evidence of it. It is possible that the Carper was claimed but never worked.
The minerals I found at the San Diego are anglesite, augite, calcite, cryptomelane, galena, hematite, hemimorphite, limonite, quartz and wulfenite. There are more listed for the group but a number of the minerals we never did see in the dumps. They mined the metallics in the main veins, mostly galena, which was taken to be processed and not much is left in the dumps. I assume some of the minerals listed we didn't see were in the main ores that are now gone. After collecting here several times I discovered that the wulfenite was associated with the yellow limonite and looking for wulfenite it was best to look for the yellow limonite bearing rock, which was not very plentiful here. One nice discovery at the mine while looking through the rock at home was a small specimen with the layers of colorless hemimorphite in all the cavities and in one field of these crystals was a yellow wulfenite. When I looked at the pocket under the microscope I saw the wulfenite was pierced through by a number of the hemimorphite crystals. It is my favorite wulfenite from the San Diego Mine. When you look at the himimorphite it looks white against the host rock but the crystals are actually colorless. There was one spot at the San Diego Mine that a load of ore had been dumped. This spot was now covered by a lot of brush but it was a spot separate from the main dumps and in this there was a lot of the hemimorphite material.
One thing we have found was that at a certain time of year collecting at the San Diego Mine was next to impossible. When the summer rains had been good and the conditions were right the tiny biting flies called no-seeums were out in great numbers. They were as tiny as grains of ground pepper but they had a nasty bite and loved flying around the face and biting on the head. When these flies were in their height of season it only took a minute for them to find you and you were covered by hundreds of these biting flies and it was time to leave. Luckily their season lasted only a few weeks and they were gone again. We have been driven from mines on numerous occasions by these biting flies when the conditions are right. Since Mary has a bad reaction to the bite of these tiny flies we didn't stay when they are out. For some reason, the San Diego Mine area is right for them when there has been good summer rain. One trip to the mine also had a Gila Monster crossing the road and it is a good habitat for rattlesnakes. There is one other thing at the mine and while collecting ones pants, shoes, socks and anything within a couple of feet of the ground gets covered by a sticky plant called stick leaf. The plant has tiny, velcro-like fuzz on the whole plant. It is to spread its seeds and the plants get stuck to anything that brushes by them. I am sure it is useful when mammals walk through the plants and the pieces get stuck to their fur. It is only a bother since you get full of this stuff and it is not easy to get off. When the plants are green it is even worse because when attempting to remove the green plant parts they squish easily and leave green streaks all over ones clothes. I have found a knife blade is best for running along ones clothes to scrape off the plants. Of course care must also be taken here. The worst seems to be shoe laces and those get covered by the plant parts. The San Diego Mine has lots and lots of these plants. Getting busy collecting one can easily get distracted by the minerals and end up covered by this plant.
The San Diego Mine has a small story with it and it is about the time my father was no longer able to live by himself and he was at an assisted living home near us. At the assisted living was a man we got to meet and talk with named Harry Hughes. When we talked to Harry he talked about living in Tombstone as a young man and actually owning a mine there at one time. He mentioned the name San Diego Mine and at this time I only knew the group name of Tombstone Extension and when I researched where the San Diego mine was it turned out to be the one we collected at the most. I brought Harry a piece of ore from his former mine and he was happy to talk about the early time when he was working the mine. It was nice to actually meet one of the old owners of the small local mines I had actually visited. Unfortunately his memory was very bad and he didn't remember many of the details I asked him about when he had the mine. He said he had no knowledge of minerals and had people who worked the mine for him.
Past the small group of mines when I first visited in the late 1970's, the road continued toward the hills behind Tombstone. There were many side roads and at the time I used a VW bus to navigate all the dirt roads of the area. There were no homes in the area of the hills and the road was not posted at the time. The only fences in the area were cattle fences and most of those were not kept up. Getting close to the hills the roads diverged and one branch went West and into the hills of the main mines of Tombstone. I did take the roads here one time in later years with my ATV and stopped at a number of the small mines. I never did find much in the way of interesting ores at these small mines, mostly the black manganese ores of the district, calcites and quartz.
Up the side road to the SE was a mine called the Morning Star Mine. I did stop and collect at this group of mines, which did have a decent size ore dump. I found mostly manganese with a few pockets of white calcite but not much in the way of collectable minerals. One trip with my brother in law we went up to some of the mine dumps a little way from the main Morning Star Mine dump and Winston found a specimen I envied, a nicely vanadinite with well formed crystals. I went back to the spot at a later time but was never able to find any more vanadinite. The dumps of this area are fairly barren of minerals.
The road continued E. into the hills and then split again. One road went up and up and finally got rough enough I turned around. No mine dumps of any size were visible on the hills above even though most of the roads in the area went to small mines. The small fork of the road that went to the NE from the main canyon road was also quite rough but drivable with my old VW. It went up and up and finally ended at a small spot where I think they had done some exploration drilling. A quarter mile from the end of the little dirt road was a small mine dump. We stopped after turning around at the end and the dump was mostly limestone but there was a lot of calcite in thick brown to light brown seams in the dump. The time I stopped at this little mine was in Winter and although the sun shone it was a cool day. While collecting calcite on the dumps bees came over to see if we had anything sweet to use for their hive. I went to the small shaft and looked in and saw that the bees had a hive in the mine. The dumps contained some cave formation pieces, small stalactites and I knew that down below they had hit some cavities. Since the bees lived in the mine I never considered going in to see if there were caves in the mine. The bees had all been Africanized so it was not a good situation. Collecting at this dump was always an adventure since there were always bees flying but they were mostly interested in moisture and we never did get stung. As long as you didn't swat at them they usually left you alone. We also stayed away from the actual shaft since that may have been too close for the bees and we worked to collect in the dumps below the mine level. The bees were here for over 25 years and only on the last trip were there no bees. When I got the calcite home I found it was fluorescent and what was interesting was that there were two kinds of fluorescence. Both were under short wave UV but one was a light orange glow and this kind was not phosphorescent. The other was a light yellowish-white color and not nearly as bright as the orange one but it was phosphorescent and glowed for a brief time when the light was turned off. Funny how there were two types of fluorescence at this one location. The Calcite was the only thing we found on the dump and the mine was not big.
In later years the road got worse and worse until it was no longer drivable by 4 wheel drive. Every time I did visit the small mine the bees where there. The last time I visited the mine was with an ATV and the bees were gone. Since I didn't have equipment along I didn't enter the mine to look for any cave entrances. Since then the area has built up with several homes along the hills closer to the highway and the area has been posted and the road that went through to the calcite location is now blocked off.
This build up of houses in the area has made the area less open and we have not been to the mines here in a number of years now.
There is one other thing of interest with this area. While on one trip at the right time of year there were some flowering bushes by the road and I knew what they were. The plants were actually quite pretty for the normal desert shrubs. They had very large leaves, nearly hand size and palmate that were bright green with tiny spines and white dots on the leaves. I had my camera along and stopped to get a few photos. I was telling Mary that it would not be a good idea to touch the plant when she said it was already too lake and her hand was already on fire where she had brushed against the plant. The plant was called Mala Mujer and had a very nasty sting from its spines. The reaction resembled that of stinging nettle and was well known for the sting it could give. Mala Mujer means bad wife in Spanish, most likely named by some aggrieved husband where the plant is common in Mexico. The plants can be up to a meter high and the leaves and flowers are pretty for a desert plant. The hill up to the San Diego mine was a perfect habitat for the plants and we have stopped several times in the area, not to collect minerals but to see if the plants are in their flowering stage. When we pass by this area we often think of the plants and not the minerals we have found here.
The San Diego mine is now closed to collecting and my early time here let me find some interesting things. The buildup of homes in the area has also made it difficult to get access to the areas beyond any of the houses. There are still ways into the area but the access is very rough and not easily reached by anything but an ATV. The minerals I found in this group of mines is not as complex as those from other small mine of Southern Arizona but just being able to collect in the Tombstone area was a treat.

Article has been viewed at least 1768 times.


Rolf, your collecting stories always entertain and interest me! For anyone else who might come across the nasty plant "mala mujer", here is a photo. Please keep writing, and thank you!

Becky Coulson
17th Dec 2016 10:26pm
Interesting read Rolf. It always amazes me how good your memory is!


Steve Sorrell
23rd Dec 2016 10:57am

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