California, USA

David,

Walnut Creek is a nice place to visit. You can educate yourself on Mindat by searching on "Contra Costa Co., California." This will give you all locations in the county, including those nearest to Walnut Creek. If you go into the individual files, you will have all of the information we have on each location and its geology. You will also have all of the references for those localities (listed under the county file). Since you will be close to San Francisco, you can stop in at the Division of Mines and Geology in the famous Ferry Building. They have a large collection of California minerals and an extensive library with the references. Please remember that California is a project in progress and more information will be added in the future.

Chet Lemanski

Chet,

Thanks you a lot. You give me good information about what locality i should see on mindat =) I sure i have to go to Ferry Building in San Francisco
soon...

Thanks,
David.

Chet,
excuse me but i missunderstand about individual files and referens. I know that i can see list of referens in almost each locality.

Thank you,
David.

David,

There is also a list of references under the county level file (Contra Costa County). Many are duplicated in individual files. The county file list makes it easier to see all of the county-wide references in one list.

Chet,

Please check the grid reference of the following locality:
[www.mindat.org]

Peter,

I just started working on Del Norte County yesterday. This file will be scrutinized in turn.

Chet

I am finally done with Siskiyou County and its 1,900+ localities, more than any other county, many states, and even many countries. It took slightly over 3 months to get it done. Next will be an easy one - Modoc County - I need a break.

Chet

Wow Chet, awesome work on the California localities! I know many of them well.

Once on this thread, I noticed earlier references to the mineral collection at the Ferry Building in San Francisco. Unfortunately, that was moved and the display collection was drastically downsized in 1983 when the powers that be decided to move it to a new California State Mining and Mineral Museum housed in Mariposa and part of the State Parks. Well, it is now scheduled to close in 2012 as part of the California State Park closures aimed at reducing costs. These moves, together with the demise of the California Academy of Sciences display, have literally pulled thouisands of displays specimens away from view, opened up the collections for pilfering and back-door deals (none sanctioned, of course), and relegated great specimens to the dark abyss of rolling lock-boxes and storage units. Bummer!

Just wanted to set the record straight on the Ferry Building, but got on a bit of a soap box there, didn't I?

Cheers from NorCal, John

"God gave me the stubbornness of a mule and a fairly keen scent." - Einstein

John,

Thanks! I obviously wasn't aware of the Ferry Building issue. Too bad! It is a continuing trend in many places. Arizona just did the equivalent with their state display and the Philadelphia Academy de-accessed a chunk of the Vaux collection a few years back.

Chet

Chet, I think you have been violating our no more than 60 hours a week rule.

Rock Currier
Crystals not pistols.

Modoc County is finished! That was easy. It only took a week. I'll decide which county is next after the 19th.

Lassen County done - on to the next!

Hi, I just inadvertently deleted the message i spent most of an hour writing...and as I'm now so steamed as to be ready to scream [I hate it when that happens...] I'm just going to be brief and anyone that is interested in any more info can arrange to contact me by phone or something whereas I won't have to write or type [as i am a writer presently on other subjects, keyboard time is of a precious outlay of energy.]
My folks have owned a parcel [2.6 acres] of land on Grannite Ave. in Orangevale Calif. since 1976. The parcel is divided into two sections by a natural creek, Linda Creek. Linda Creek used to dry up in the summers until the late 1980s. This property is literally right at the base of the Sierra Mountain foothills as the hill that rises right behind my folks property is the last such rise from there to the western edge of the Sacramento Valley. Along Cherry Ave that intersects with Granite some 90 or 100 feet from my folks place is a section of fenced pasture to which said hill abuts and that picec of land along Cherry Ave goes back and then behind the private homes and rural property , of which all are no further back than a hundred feet or so along Cherry Ave is a State owned preserve known as 'Indian Stone Corral. It is a huge maze of swollen finger like or oblong and stretched fat egg shaped granite boulders that boil up out of the ground at the base of the hill that abut one another so tightly as to be impenetrable and they form a maze around sections of flat grassy areas and some dead end ...hence the term 'Stone Corral' as they were probably used as such at one time...and it apparently was a favorite location for the local tribes people in the past as you could easily get lost in this maze and or hide as to which you could only be found by knowing the ins and outs or by happenstance. The entire area between Cherry Ave, in Sacramento Co. on the south to Douglas Blvd. on the north in Placer Co. bordered by hazel Ave/Sierra College Blvd on the west and Barton Dam Rd. on the east was still wild and undeveloped until recently. In the late 80s, Linda Creek which cuts across my folks property quit drying up in the summer months and as the folks had had trouble with the creek flooding very damagingly and surprisingly so as to the extent of amt. of water [between 3 and 4 ft deep and some 30 to 30 yards wide for a day or two] 4 times between 1976 and the early 1990s my folks and the neighbor on Cerry Ave that borders Linda Creek complained to the County gov't and got no answer or explanation as to why it was now running year round which caused much concern as any future flooding could expect to be even more damaging [a long story of development and politics involving both Sacramento and Placer Co. Supervisors which I'll skip]. My father, our neighbor on Cherry Ave, and I, we all put on waders and decided to follow Linda Creek upstream, to hopefully find the fount as no maps were ever accurate made of the immediate area it turned out. [The actual head or fount is an area about an eighth to a quarter mile west of Folsom Lake Dam at a point [that can now be found on maps]known as Barton Dam...apparently it is a spring that comes out of the ground and then runs south and west in a general very snakelike manner eventually finding its way into the Sacramento River somehow ...to the west.
We probably got about an eighth of a mile, give or take, up stream from the granite corral area and it started to get narrower, deeper and too much overgrown to continue and I seem to recall that it was skirting along the base of the hill i mention at the beginning of this post and at that point I noticed on the banks of the creek on the north side was a mine shaft that was cut into a small rise of the skirt of the hill and which appeared to go in and down at an angle into the earth or side of the hill which had granite columns and a granite lintel framing the entrance.
I contacted a gov't agency a month or two later [I believe it was the Bureau of Mines..but don't recall exactly] about this as a 'Curiosity and something of much possible historical significance..and as it was in an area to which one had to be most determined to get to [waders upstream!] and is, for a fact, a rather slow, arduous and frustrating hike I doubted it would be accidentally discovered by kids... and the lack of development in the area pretty much assured that...till now. The agency requested that I get a topo map of the immediate area and pinpoint its location and My efforts at obtaining any such map was met with total frustration [apparently none are to be had or there never were any actually produced of the are up till that time.] and when i contacted them again and requested someone to come out and see for themselves I was met with a rather sarcastic reply that due to some voter initiative or something like that they didn't have the manpower or even that much time as I had already had them commit by talking to me on the telephone....[In fact I got the impression that he believed my story to be nothing more than just that...A Story...or something I thought to be a mine but in fact was something else...as he scoffed at my description of granite columns and lintels.] All the area north of Cherry Ave and also on the Placer Co. side of the county line has been developed and the buffer area between placer Co. and Sacramento Co. that the High Power transmission lines run through and which we were under the impression was also a 'green area' which wouldn't be developed has apparently been okay-ed for some sort of development [don't ask me how or why?] and thus I am now concerned that ..as Murphys' Law will not be denied...and I'm sure most of you will agree...some kid or bunch of foolish kids {or even adults} will stumble upon this in little due time and ....!?!?!?..
As I did do some panning on my folks property in the alluvial like deposits left by the flooding from that winter around the large oak that grows partially in the creek bed in the 90s and found to my delight a small but large enough to be identifiable piece of flat ribbon barbed wire [about the size of two typewriter keys across and one wide] I know the area to have been inhabited by settlers from at least the 1880s. and has remained relatively unchanged in the area till the present this mine could be from around then. Or possibly older as it is about 2 miles or less west of the American River and slightly Northwest of the old town site of 'Nigger Bar' or present day historical Folsom...and I understand Oak Ave. to the south of the folks a half mile was an old stage coach route with a stop at a site just a few yards west of the intersection at present day Oak Ave. and Hazel Ave.
There is also a local legend that one or more of the notorious bandits of the 1800s in Calif used Indian Stone Corral as a hideout...and that possibly one of the still missing hauls from a stage robbery that is alleged to have been rather large is possibly buried in the area.
..all in all ..Who knows...
Anyone interested in checking this out for themselves or wishes more info on this can contact me at. piercethevale@yahoo.com ...please title the subject of your e-mail as 'Indian Stone Corral' as I get a tremendous amount of spam at this e-mail address which I use for all correspondence other than personal...anything not identifiable as other than spam from the subject title is deleted as I do not open unsolicited and or questionable e-mail.
Thanks,

Dave,

The mine shaft is one issue, but perhaps the bigger one is the intermitttent stream, now of continuous flow! You mention the "spring" near a dam. I would certainly fear that the dam may be compromised either due to the mine workings in the area or simply an inadequate foundation which is now being undermined by the water pressure. That is what the authorities should be looking into. Remember the Johnstown, Pennsylvania, flood. That dam also started leaking around the bottom before giving way.

Does anybody know where may I explore and collect ophiolites somewhere in Contra Costa Co. or Alameda Co.?
Thank you,
David.

As far as I can tell, there are no ophiolites in Alameda County.
On a map of ophiolite outcrops I've seen in the book "California Geology" by Deborah Harden, there was an ophiolite patch at Mt Diablo, that would be Contra Costa Co. It is also a state park, so collecting might be prohibited. I remember a vvery small exhibition of local mineral and rock specimen in the Mt Diablo visitor center (many years ago), might be worth to check this out.

There are small ophiolite outcrops in the southern part of the Bay Area, and to the northwest in Marin County, even in San Francisco (but you wouldn't want to start digging on Union Square).

I've never checked these outcrops out myself, though.

Hi everyone!
I have been in Mt Diablo State Park.
So I found only one place with th blue schists.

David.

I just added a reference to the Mohawk mine, San Bernardino county locality. In 1990 the San Bernardino County Museum published a 32 page booklet titled "The Mineralogy of the Mohawk Mine, San Bernardino County, California" by William S. Wise. It is Quarterly Vol 37 #1. It is still available from the museum bookstore but I have no idea how much longer. Its a very good write up on this locality and I ordered mine a few weeks ago. If this is the wrong place to post this please move or remove it.

Bill Wise was/is a careful and accurate researcher and is we should be glad to have any work done by him referenced in our database.

Rock Currier
Crystals not pistols.

Shasta County is now "finished." I have already started Trinity County. The California project marches on!