Last Note From Plymouth: Siderite Sighting?

This odd looking lump is on my friend’s horse ranch on Carbondale Road, outside of Plymouth, California in rural Amador County. Near the center of California’s Mother Lode Country. I wrote about this place in a previous post. The soil is nondescript, red foothill clay, with the most common rock underfoot being broken pieces of iron stained quartz.

And then there is this thing, which my first guess was a bunch of leftover concrete that someone had attempted to color. Perhaps they dumped out their concrete mixer at this spot? There is no sign of any unusual concrete work in the area, but who knows? I did not have my rock hammer as I was traveling and renting a vehicle.

Usually concrete aggregate has much smaller stones than the blobs we see here. I am up to any guesses. There is a creek nearby with what I presume are rounded stones but it is not on my friend’s property so I haven’t checked it out. I can’t imagine anyone making their own concrete with locally collected rock, think of the work, but I suppose it is possible.

Another possibility is siderite, which Mindat.org lists as being in the general area. A nice man named Brice on the Facebook group, Rocks and Minerals – identification and information, made this suggestion.

Siderite is an iron mineral, of which I am only now reading about. Apparently, siderite is valuable mineral in theory since it contains a high amount of iron, possibly 48%. In such a small outcropping it is totally uneconomic but an interesting curiosity to any rockhound or mineral collector walking the woods. Its presence may lead to the discovery of other nearby minerals such as manganese.

The odd looking lumps may be large siderite crystals that have weathered to their present shape over time. More on that below.

 

This is an overall view of what I will call for now, the outcropping. For a much larger picture to ponder over, click here. Or click on the photo itself.

 

Closeup photograph. Pen for scale.

 

A damaged or otherwise altered section of the outcropping. Broken concrete doesn’t turn black, it retains a whitish color due to the Portland cement. If the concrete were mixed with a colorant originally, however, in the drum, the color would run throughout the mix.  But you would have one color, and not two as in the photo. An iron ore deposit just might make sense. The outer layer has weathered and oxidized red, rusted if you will, while the more newly exposed material has yet to change.

 

The above picture is courtesy of Dennis Miller. Used with permission. It’s siderite from an area near Chihuahua, Mexico. Note the globular forms. I’m speculating that the globular material in the outcropping I came across are weathered, eroded permutations of this siderite’s original form. Or not.

The Henry Holt Guide to Minerals, Rocks, and Fossils (very British) says that siderite crystals can be, “[M]assive, fibrous, compact, botryoidal, or earthy.” The outcropping seen here is definitely botryoidal.

The book goes on to say that massive siderite is widespread in sedimentary rocks, however, this area is in the Sierra Nevada foothills, granite, quartz and slate country. Judging from my experience in nearby El Dorado County. There are notable, economic clay deposits several miles distant, which leads me to this quote from Holt’s book.

“Massive siderite is widespread in sedimentary rocks, particularly in clays and shales where it forms clay ironstones which are usually concretionary in origin.”

Concretionary. And an outcropping that looks like concrete. Iron stains every piece of broken quartz on the ground. So iron must be in the soil. Can anyone put this all together?

Mindat doesn’t show siderite as found in Amador County, however, these reports are usually confined to recording occurrences of economic value. Or a citation in the scientific literature. Like in a geology report. Not all outcroppings everywhere can possibly be recorded. Siderite has been reported in the county of El Dorado, immediately north, and Calaveras, immediately south. In the plant world, we would call an occurrence in a new area as a range extension. And you thought rocks and minerals had a peculiar vocabulary!

I am waiting on a local rock and gem club member to tell me what he thinks the outcropping is. And I will have a friend test the outcropping with a magnet. That may be diagnostic. Although I see on Mindat that siderite is paramagnetic, a new term for me. It essentially means weakly magnetic. I’ll mail my friend one of my rare-earth magnets. Maybe that will make a difference in testing. I’ll report back later. Thanks, again, Dennis, for the photograph.

Greetings From Plymouth, California

A few days ago I had to leave Las Vegas on an emergency trip to help out some friends. The couple I know owns a hundred acre horse ranch in Amador County, in the Sierra Nevada foothills. Their spread is near Plymouth. The heart of California’s Mother Lode Gold country.

When this husband and wife first bought their property I came out with my gold detector. I was delighted to find broken quartz everywhere. Most displayed iron staining and many contained vugs or cavities.

Alas, only a small speck or two of gold was found in a shallow ditch running through the acreage. The nearby creek had been dredged for gold but my friends didn’t own any of that stream. Nor did they own property containing any tailings.

Never-the-less, the many small pieces present might be useful one day for tumbling, as their dark vein patterns contrast nicely with the quartz matrix or host rock. Even if you can’t find gold, you can often find something else.

Iron staining and vugs are signs of mineralization and activity within a rock. Something has acted on the stone. Most quartz is barren, white colored with no character. Sometimes called bull quartz. You look for character when you look for gold. Decomposition or crumbling quartz is another sign to watch for.

Having said all this, the finest gold in quartz I have found displays no other minerals save a scattering of the gold itself. My specimens are milky to near pure white with only gold showing in the matrix.

The lesson is that if you have the time, detect all quartz, even that which looks sterile. If you don’t have the time, limit your search to quartz that shows mineralization or the effects of forces which have altered the rock.


 

The quartz on the left shows iron staining, the material on the right shows vugs. These have not been cleaned and both show the clay soil of the area.


 

The larger rock might make one or two interesting slabs. The smaller pieces might be tumbled.

 

 

Latest Spot X Firmware Update Available

Time for all Spot X users to update their firmware. Let’s make certain you know how to do this.

1. Download the device updater  to your computer and then install it. Run the program. Do this first. THEN

2. Connect your Spot X and follow the instructions presented.

Again, download the latest version of the updater program first, then connect your device. DO NOT USE an old updater. You must download the newest updater first.

My device appears to be working well after the update.

This is what Spot X says in their latest e-mail:

In our continued effort to ensure the best possible SPOT X user experience, we have made some updates to the device firmware V1.7.14 and the device updater 1.12.8 to improve usability and overall intuitiveness. You need to first download the latest SPOT X device updater. Next, connect and update your SPOT X firmware to start benefiting from these upgrades on your next adventure. Below are some of the update highlights.

My Four Hundred Dollar Rock

Truly, the best things in life are free.

I recently went on a fee dig at the Cuesta Fire Agate Mine near Oatman, Arizona. Don Nelson is the claim owner there, with Old Route 66 passing through the center of his four twenty acre claims.  Don was warm and personable and I and several other rockhounds had a great time. I’ll report about this adventure with lots of photographs in my book.

I left Don and the group in mid-afternoon to go to Kingman. I regretted that I hadn’t bought any fire agate rough from Don earlier at his house, some distance from the claims. But I had photographs and at that point I really needed to get going. And I also needed a diet Pepsi.

Several miles down the road a classic Route 66 store appeared, named Cool Springs. A sign promised cold drinks. I bought a diet Pepsi for two dollars and tipped the rustic, picturesque looking character at the cash register an extra dollar. His face lighted up at the tip and he thanked me.

Outside, I noticed a few tables covered with rocks. There were several pieces of fire agate rough, material that looked just like what I had seen from the claim. One piece was pretty but had no price tag. I went back to the cashier who I now assumed was the owner. I declared that I was back and asked how much he wanted for the rough. He asked for twenty dollars which I promptly paid. I’d now have something to take more detailed pictures of in my photo box at home.

As he considered the stone, he started to list the challenges of working fire agate, of removing the chalcedony to reveal the stone within the rock. Not all fire agate flashes, and inexpert carving might remove the thin layer that produced the play of light.

He asked me if I had done any carving. I said the only rock I had carved was my jade key fob, done months ago. I handed him my keys and said somewhat apologetically that it was supposed to be a leaf. He examined it closely and said that it was really nice. That made me happy. By the way he talked I could tell I had met a passionate rockhound. A kindred soul.

I walked out into the beautiful day to my truck. From behind me I heard him yelling at me to come back. He had left the register and had a rock in his hand. “Here, take this,” he said. “It’s not fire agate but it’s an agate. And it will work up real nice. Make a lot more money from it than that other piece you have.” I was touched by my his gift and I thanked him. As I opened my truck door, I could hear him calling again in a laughing voice. “Remember, if you get four hundred dollars for that rock, I want you to come back and give me some of that money.”

I promised I would.



 

A Little More From Oatman, Arizona

Sixty years after this article was published, the area near Oatman is still producing fire agate. If you’re willing to work at it. I mean, really work at it, with sledges, chisels, and breaker bars. Out in the field, you’ll find promising rough, the agate fixed to its host rock. On the bench, it’s lapidary skills and some luck to produce a finished piece that might flash red. I’ll report in my book on a fee dig operation that puts you on the path to this goal, finding a rock that properly worked might turn into a fine example of the king of agates.

Jade Piece Drilled Out

Some may remember that I took a jade carving class sometime back. That class resulted in my first rock carving, pictured here. We were asked to carve our idea of a leaf. I meant it to be a key fob.

 

Now, thanks to the talented lapidary artist and jeweler Jason Fabbi, my piece has indeed become one. Jason drilled a neat hole at the top of the carving with a drill press using a special bit and plenty of water. Unlike wood, drilling stone requires patience, as the bit must be inserted slowly, operated for a while, then backed out. The procedure repeats itself until the work is done. Thanks, Jason!

 

The result.

 

I have also commissioned Jason to do a one-of-a-kind piece for me. It will be a bolo tie with the center stone made from gold in quartz that I found years ago. More on that in future posts.

What Does an Agate Look Like?

Agates occur in nearly every state, along with countries around the world. Their patterns are endless and often striking, sometimes unbelievable. Right now there is a great agate thread going on on the open Facebook group Rockhound Connection:

https://www.facebook.com/groups/169785333057/

Make sure to check out the posts. They are all variations of quartz.

As beautiful as some of these cut and polished specimens are, many beginners are confused as to what to look for. Although not always present, a certain translucence and a wavy character to the rock are good signs. Some agates are so outrageously striped that there is no doubt as to what they are.

Here is a video of an agate that I liked so much that I have never had the heart to cut it open. The second photograph shows another agate from the same location, one I cut into a slab with a rock saw.

Both of these rocks are for examples only, they did not come from the Southwest. But if you are ever in Northern California, you may want to check the riverbed of Cache Creek in Yolo County. Good luck.

https://www.yolocounty.org/general-government/general-government-departments/parks/parks-information/camp-haswell

Uncut agate. Click on image or text link below. (Movie)

Cache_Creek_Agate_green

Cut agate:

Quartzsite is Here and The Fun Has Begun!

‎Neal Behnke‎ is writing daily reports to the Rockhound Connection on Facebook, a group worth following. Here’s Neal’s latest:

Welcome one and all to day 7 at the wonder in the desert, Quartzsite! Uncle Neal will stamp your passport and show you the door.

Quartzsite Arizona is really a rock hounds dream, established many years ago by wandering camel farmers, it has had a continuous rock show going since John Denver left and moved to Colorado and got all weird. First tourists started stopping as the freeway was slowly built, sometimes they would wander into the desert, sometimes they would wander back with rocks they would then sell to other tourists for water and trinkets. After 1978 the freeway reached almost a mile past town and the city was named.

Quartzsite is a fantastic place to rock hound, the local rock club (friends of Quartzsite) offer rock hounding trips, volunteer to clean the public bus benches and hand out cheese sandwiches. Please be aware if you are approached by anyone saying they will take you rockhounding, ask to see their cheese sandwich. Last year over a 100 rock hounds were tricked into looking for valley opal and 12 swimming pools were built. It is a good chance that if you are standing in someones back yard with a shovel and you are within 10 feet of wifi and a coffee maker, you are not rock hounding.

Todays Desert gardens events include Escape Room! held on the Lido deck, your goal is to try getting out of the house, finding the keys and your rock hammer and avoiding all your adult responsibilities so you can wander in the desert.

If you purchased any Cinnabar from Toxic Tonys minerals, please be aware that testing has confirmed that this particular material is hardly toxic at all, if you would like the high grade stuff please come back this morning.

Kids events today include buckskin Willys scorpion ranch! Willy has rustled up some 1.2 million desert red spotted viper scorpions, all in his .01 acre spread! Its fun to watch the little buggers tear across the desert floor, if you lean close over the 1 foot fence you can hear their tiny feet skittering in the sand!

Milking and stampede starts today at 1.

Update on The Gemfield Gem Claims in Goldfield, Nevada

My second article for Rock & Gem Magazine was on the Gemfield Gem claims outside of Goldfield, Nevada. The claims are a major source of fine chalcedony. Sharon Artlip, one of the two claim owners, now has a website for the property:

http://www.gemfieldnv.com

A month ago I visited Goldfield. I couldn’t connect with Sharon, who may have been out of town Sharon no longer operates Goldfield Art & Business Services out of the store on I-95.

The present owners of the new store at that location, however, will accept your registration and rock fees. Their names are Sherri and Mike. They have a nice store with some maps and some rocks. When I was there they had locally mined pyrite. Stop in and check out a new business:

Wild Inspirations
306 Crook Avenue
P.O. Box 121
Goldfield, NV 89013

775-485-3789

Wildinspirations@outlook.com

This is the information site at the claims.

Also, when in Goldfield, never miss a chance to check in with Bryan Smalley at Hidden Treasures Trading Company. He may be hard to find away from his store, but ask locals where Bryan is. Try the Dinky Diner. He’s well worth tracking down to visit a one-of-a-kind rock shop:

https://www.facebook.com/HiddenTreasuresTradingCo/

489 S. Bellevue Avenue
Goldfield, Nevada

775-485-3761. Honestly, I have never been able to contact him on the phone.