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Post by stoner on Dec 13, 2012 19:29:40 GMT -5
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Sabre52
Cave Dweller
Me and my gal, Rosie
Member since August 2005
Posts: 20,466
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Post by Sabre52 on Dec 13, 2012 21:28:14 GMT -5
Kris, My old Bulletin 173 Minerals of California lists occurrences in Alameda, Contra Costa, Humboldt, Los Angeles, Mendicino, San Benito, San Diego, San Luis Obispo, San Mateo and Santa Clara counties, pretty much the entire coast range. I may have seen something very similar in Big Sandy Creek near San Miguel and around Parkfield and Creston but never thought it would cut cabs. Seems to be pretty often associated with those glaucophane shists...Mel
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hand2mouthmining
spending too much on rocks
Purveyors of California Gem Rock
Member since September 2011
Posts: 495
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Post by hand2mouthmining on Dec 13, 2012 23:20:54 GMT -5
Mel, I wouldn't be surprised if you'd seen some of the Lawsonite conglomerate throughout the West Coast watershed. It's that common, an "indicator mineral" for deep subduction and catastrophic upthrust ... Which pretty much means the entire west coast, from at least Santa Catalina to at least British Columbia. We hope that, now that the Identification is in, rockhounds will find it in a great many varieties. It tends to be uuuuuugly on the outside, but so are geodes and thunder eggs, which it resembles in the rough. I guess that there are just so many good looking jades, jasper, agates, cherts ... yeah, you can easily overlook the ugly rocks! What's baffled me is that it's not strictly "new," just not identified as a lapidary quality stone. Heck, when I brought in the first nodules, the (self proclaimed) "old timers" said, oh, that's diabase! And they even got mad at me when I brought in Mindat printouts on the REAL diabase! *L* Their comment on the lapidary grade Lawsonite? "Oh, we used to cut that, but gave it up decades ago ... It's ugly on the outside!" Ohhhhhhkkkkkaaaaaaayyyyyyyyy ... So, we decided it might have a future, and some folks like it. And that makes me n' Al happy. Personally, my biggest happiness is based in getting a great GIA Identification Report! It was a total surprise, and a great Christmas gift for me. If you'd like to try some out, see our posting in the Sales section this weekend. Thanks for the stimulating conversation, Mel! Kris
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Sabre52
Cave Dweller
Me and my gal, Rosie
Member since August 2005
Posts: 20,466
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Post by Sabre52 on Dec 14, 2012 9:34:09 GMT -5
I do find it interesting that more lapidary materials are showing up now days that perhaps we would not have bothered with a few years ago. I've been cleaning out my broken milk crates of rough and yesterday I stumbled across a stream worn boulder of "Wyoming pink Jade" which I think is actually a form of thulite. The exterior is rough and ugly like a pink and green granite. Never would have thought something like that would cut until I slabbed and worked some. It is mixed hardness and does not take a mirror polish in most instances so I'm not crazy about cabbing it but it does make a sort of pretty stone. Same way with llanoite, Mariposite, and unakite and a lot of the granite type materials. Quite a few interesting materials out there if one is willing to take some extra time to work them.....Mel
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Post by tandl on Dec 15, 2012 9:43:13 GMT -5
Cool rock . It is not Granite . It is schist-Blueschist . Lawsonite,Glaucophane are metamorphic minerals . Granite is a igneous rock-Lava .
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hand2mouthmining
spending too much on rocks
Purveyors of California Gem Rock
Member since September 2011
Posts: 495
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Post by hand2mouthmining on Dec 15, 2012 23:00:17 GMT -5
Ed, I'm sorry my reply made you unhappy. :serious: The severity of your post brought out the humorous sarcasm in me; my rocks are like my children, and I defend them as such. No right or wrong there, no excuse made ... That's just how I am. No offense was intended, I just couldn't imagine an experienced lapidary and field collector such as yourself would seriously suggest that the geology of Yosemite and the Panoche Hills were anywhere near the same. The depth of available studies and reports make very clear the geologic nature of this area, with repeated subduction and "catastrophic" upthrust events the basis for my evaluation of the likely genesis of our lapidary Lawsonite rock. The results of the GIA Identification Report clearly made that opinion more likely correct, and I'll stand by them until professional petrologists tell me otherwise. We have found one or 2 pieces of white graphic granite out in Little Panoche Creek, but it's very rare. To my knowledge, the Panoches were not an area that experienced glaciation, and though some granitic pluton emplacement occurred in the nearby Clear Creek geology, to my knowledge they're not widely noted in the Panoche Hills. The single chunk of white granite I've found is composed of stark white quartz and feldspar with black hornblende crystals, and is pretty soft, unlikely to have survived much alluvial travel. My offer of hosting you was honest and heartfelt, one that I've made to many rockhounds. In fact, Bob M. mentioned he'd spoken with you, and urged you to come down and collect at Area 54. I hope that you'll take me up on my offer, you'll find rock that you'll enjoy. The best of fortune to you, Ed! Kris "If you prick us, do we not bleed? if you tickle us, do we not laugh?" - W. Shakespeare, The Merchant of Venice
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Post by geoff on Dec 16, 2012 0:45:44 GMT -5
I don't know. I think your decision to name it Gem Lawsonite is misleading at best, and that's what bothers me about all this. If I bought 100 grams of sapphire and 100 grams of gem sapphire, I would expect the gem grade to be of high quality single crystals, while the non gem grade would be bound for the tumbler. Gem typically denotes a higher grade material. If I bought gem Lawsonite I would expect it to be the exceedingly rare we'll formed crystals. Not a lump of metamorphic rock that requires GIA analysis to identify the "gem" content. If I sold Gem Olivine, would you expect peridot or dunite?
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Post by stoner on Dec 16, 2012 3:00:01 GMT -5
Each cab I cut is like a child to me too, therefore, that's why I only use top quality material. I have cabbed some of this Lawsonite and I don't find it to be top quality material. Having grown up in the Bay Area, I know what's available in northern Calif and there's not much that's worth cabbing. Thank you for your offer of rockhounding in your area, but I'll pass. I don't even think I know of a person named Bob M. let alone a conversation with him urging me to try collecting at Area 54. Now if you'd like to invite me to come down to Arizona or Woodward Ranch to collect some rock to cab, I'd jump on the chance to collect some quality material.
In short, my objection here is the way the material is being presented to the members. A spade is a spade is a spade-call it such.
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Sabre52
Cave Dweller
Me and my gal, Rosie
Member since August 2005
Posts: 20,466
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Post by Sabre52 on Dec 16, 2012 11:17:52 GMT -5
Just anther little addition to the conversation but actually, just west of Yosemite down toward Hornitos in the Sierra foothills where we owned a ranch, the geology is very similar to the interior coast ranges . We had a lot of metamorphic rock including things like andalusite crystals ( both clear and chiastolite) and in addition had lots of poppy jasper and brecciated jasper from the same sort of deposits you'd find in the coast ranges ( The Hunters Valley complex). In fact, my buddy and I found a huge monolithic outcrop of red brecciated jasper that could have come from Creston, Parkfield or the Panoche hills except less fracturing. There is some really mixed up geology in the Mother load country on the west slope of the Sierras.....Mel
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hand2mouthmining
spending too much on rocks
Purveyors of California Gem Rock
Member since September 2011
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Post by hand2mouthmining on Dec 16, 2012 21:53:37 GMT -5
You aren't kidding, Mel! We get chiastolite all the way down into the edge of the foothills north of Madera, and I'm told that you can dig it from the stream beds miles out into the Valley surrounding Chowchilla. The Madera chiastolite are really good, with lots of different colors and great patterning. We'll be taking a field trip up to the digs on Road 29, on December 30th. The Hornitos poppy jasper is lovely! I've been trying to get access to the active claims for years, but never get a call back or email inquiry answered ... Bummer! Me n' Al (my mining partner) went out to Area 54 in the Panoche's on Friday, and came back with some sweet material. We found lots of jasper like this ... This is Panoche Paisley Poppy (3P) jasper, a chunk the size of a ladies fist. As you can see, it's loaded with color, lots of black metallic hematite, and cuts wickedy cabs, indeed! This one shows better poppy features than most ... Can't wait to slab it! Got to go post some sales! Kris
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Sabre52
Cave Dweller
Me and my gal, Rosie
Member since August 2005
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Post by Sabre52 on Dec 17, 2012 10:11:50 GMT -5
*L* Yeah, my prospecting buddy showed that doctor samples of the poppy jasper we had been digging form the glory hole pit and the doc went out and put our best collecting areas under claim. I told him not to shoot off his mouth about where we were collecting. Lots of jasper up there in areas not under claim though as it's scattered over a large area and the old digs are mainly buried under brushy growth so they don't show up. At least a dozen areas for poppy jasper that I know of and maybe half are now under claim. Rough country and very bad roads though especially in winter when it's cool enough to dig. I used to hike in quite a bit. When I had access through a friends ranch, the trail in was only a quarter of a mile or so. The long way in it's several miles and really steep over much of the trail so when my friends ranch sold, collecting became much more difficult.
Cool poppy sample you've pictured. really reminds me of the Big Sandy Creek material....Mel
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Deleted
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Post by Deleted on Dec 18, 2012 19:05:22 GMT -5
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hand2mouthmining
spending too much on rocks
Purveyors of California Gem Rock
Member since September 2011
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Post by hand2mouthmining on Dec 18, 2012 21:13:24 GMT -5
Thanks for the interesting links, Scott! Your research is greatly appreciated. There's no telling exactly what will show up as we have time and funds for additional GIA Identification Reports and petrographic research. It will be interesting to find what the minerals in the entire range of similarly colored and shaped materials is, though that's certain to take some years of research. The initial GIA research was done on 2 pieces of Top gem material, and there's doubtless great variation within the full range of the Lawsonite bearing material. We'll be making a point to submit the blue granite style material at the earliest affordable opportunity. My own take, after researching Wikipedia and other sources, was that we weren't looking at diabase. The 10x loupe based opinions of geologists at the local community college, Fresno State, and a field geologist with the USGS, was that it wasn't diabase. We may all be wrong, who knows? The Fresno State (CSUF) petrologist opined that the colorant in the blue granite style might be Pumpellyite, which wasn't a bad guess. However, it seemed that the material would have been softer, had that been the case. It's certainly harder & tougher than the Central Park diabase is noted to be, though the appearance is similar. We're actively seeking academic partners for further research, in addition to individual geoenthusiaists such as yourself. Your efforts truly are appreciated. Best regards, Kris
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hand2mouthmining
spending too much on rocks
Purveyors of California Gem Rock
Member since September 2011
Posts: 495
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Post by hand2mouthmining on Dec 18, 2012 22:07:29 GMT -5
*L* Yeah, my prospecting buddy showed that doctor samples of the poppy jasper we had been digging form the glory hole pit and the doc went out and put our best collecting areas under claim. I told him not to shoot off his mouth about where we were collecting. Lots of jasper up there in areas not under claim though as it's scattered over a large area and the old digs are mainly buried under brushy growth so they don't show up. At least a dozen areas for poppy jasper that I know of and maybe half are now under claim. Rough country and very bad roads though especially in winter when it's cool enough to dig. I used to hike in quite a bit. When I had access through a friends ranch, the trail in was only a quarter of a mile or so. The long way in it's several miles and really steep over much of the trail so when my friends ranch sold, collecting became much more difficult. Cool poppy sample you've pictured. really reminds me of the Big Sandy Creek material....Mel Thanks for the info, Mel! It's often frustrating to get access to proven sites and keep them open. At our field trip website, we're always looking for roadside sites that offer good collecting. The Road 29 cuts and Area 54 are just a couple of the hundreds of productive roadside sites in Central California. Anyone who has a site they've been accessing that they'd like to keep open for rockhounds is welcome to contact me for assistance. We've looked at the record of Club claimed sites, and feel that sharing with the Rockhounding Community is the best way to keep access open for all. Thanks for the reference idea on the 3P jasper, it's a new passion for me. Gotta love all that color! The geology of the West Coast makes California a jasper lover's Paradise! Later! Kris
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Sabre52
Cave Dweller
Me and my gal, Rosie
Member since August 2005
Posts: 20,466
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Post by Sabre52 on Dec 18, 2012 22:49:42 GMT -5
Kris. Yeah, access is usually the big problem. Working for the AG dept and knowing lots of farmers ranchers and associated folks was a key that opened a lot of ranch gates for me. Plus, I've got to admit, that I'm one very friendly, charming and non threatening individual and a pretty sweet talker. I speak "ranch" really good. *W* *L* and my prospecting buddies back in California were even better than me if that is even possible *L*....Mel
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itsandbits
freely admits to licking rocks
Member since March 2012
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Post by itsandbits on Dec 19, 2012 1:27:53 GMT -5
As to the Lawsonite Living in BC, every second rock I trip over is granite, and for anyone that has ever worked granite, or fractured it with a hammer, or been trying to coax a cab out of a nice pink peice and had it fall apart in their hands, all I can say is, IT AIN'T GRANITE, and you know it!!!!!!!!!!!!
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Deleted
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Post by Deleted on Dec 19, 2012 18:00:08 GMT -5
I cannot find information that diabase is a species of stone. Diabase seems to be a generic term that describes a rock that which has already "changed". That is "diabase" may be a metamorphosed stone of a number of species. The various descriptions I see indicate that 'diabase' stomes may include plagioclase feldspar, quartz...
Here is an interesting quote from Encyclopedia Brittanica:
Sphere like masses? Rounded edges and corners?
Just as "not all fruits are tomatoes, all tomatoes are fruits".
Certainly all diabase are not Lawsonite, but it sure looks to me like Kris' stone variously namesd as gem glaucophane, Blue G, and or Gem Lawsonite is one form of diabase.
I am no expert. I have simply formed this opinion from the reading available to me. I'll let others decide if Lawsonite may be a form of diabase.
And for itsandbits, please don't stress! Of course it ain't granite! While granitic stones MAY have some or all of the same constituents, the crystal structure of Kris' Lawsonite stones are far too small to qualify as a granite.
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Deleted
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Post by Deleted on Dec 19, 2012 18:17:41 GMT -5
Wait, why can't you reference Mindat? What's its purpose if not for reference? Also, congrats on the id. But for me, at the end of the day it's just a rock. Not a gem... MindatFirst described in the same hills as little Panoche Creek in 1915. It was discovered and then forgotten.
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Post by stoner on Dec 19, 2012 22:03:11 GMT -5
I was just looking at the Mindat page for Lwasonite. It said "feel free to link to this page" so I did and here it is-all the REAL info on Lawsonite. www.mindat.org/min-2353.htmlIf you click on the link for more photo's at the top of the page, it shows what REAL Lawsonite looks like. I realize this is just the mineral, but don't you think that if there was such a thing as Gem Lawsonite, it would be in mineral form?
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Post by deb193redux on Dec 19, 2012 22:19:52 GMT -5
that is the point Geoff made. Gem is usually the macro crystal. Here gem is used to denote cab-quality gemstone. Sort of like references to gembone.
I think many use the term granite to mean mixed minerals and hardness. I understand metamorphic is not granite, but if conveys the point of the good stuff mixed in with softer stuff. Like Lavarkite has nice feldapsr flash in with softer black crystals.
I still just kind of like the rock, but I buy B+ grade. Unless I had a particular project, I would not likely buy the top grade because I like picture jaspers more for slightly less $$.
I think some of the bush back and concern *Shotgonner aside) is because Kris can be a bit hyped and late-night-TV-announcer'ish as he tries to develop his business. It kind of clashes with RTH culture.
But I cut into some of those B+ grade nodules and most of the brown mud and altered stuff was in the outer half-inch. The centers are looking pretty solid, and the $1/lb RTH price was worth it. I am having some fun. Do not expect world-grade cabs, but should get some nice stones.
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