LowPoint Posted July 4, 2015 Share Posted July 4, 2015 Well, after reading a few blogs last night on "Minelab's Treasure Talk" website, I got "Inspired" by the information, and descided to head out to Lynx Creek for an hour or so. I had read some very good information by Steve Jerscbach, Jonathan Porter, and Chris Ralph. "The Tale of Greenstone Gold" by Chris Ralph got me to thinking: I know just-where there is just-the-same-type-of-bedrock he is talking about, right here on the Lynx!!! So, a little after 2pm today (this is not my most-favorable time of day to do this, as it was 85 degrees out, but the sky was overcast) I headed out. And wouldn't you know it, about an hour later the sky cleared up and the sun started baking me;.. I am sure that it was atleast 90 by the time I started to walk out at about 4pm. But, I didn't leave empty-handed, as this 0.51 gram nugget was sure-enough-hiding wedged-down about 10" deep within a crag in the greenstone outcropping....So, as a suggestion I would recomend reading some of these Insitefull blogs from these pro's, get inspired by them, and get out there and find some gold,.....It's still out there!!! Gary 1 Quote Link to comment Share on other sites More sharing options...
TomH Posted July 4, 2015 Share Posted July 4, 2015 Gary: That is AWSOME! You did the research, found the spot and got some yellow WTG!!!! Hope you have a lot more in the future. GL to ya Tom H. Quote Link to comment Share on other sites More sharing options...
LowPoint Posted July 4, 2015 Author Share Posted July 4, 2015 Hello Tom H.You guys where camping about 3-miles away from this spot when you where on your camp-out trip. I have never found anything but trash and alcoholic partier's up there in that camping area, so I find better places to detect.......like, below the dam. Gary Quote Link to comment Share on other sites More sharing options...
nugget108 Posted July 4, 2015 Share Posted July 4, 2015 Nice little nuggy. Quote Link to comment Share on other sites More sharing options...
TomH Posted July 4, 2015 Share Posted July 4, 2015 DOH!!! Its still up there. Hope you get some more from your spot Tom H. Quote Link to comment Share on other sites More sharing options...
Tortuga Posted July 5, 2015 Share Posted July 5, 2015 Interesting article on "greenstones". I know I've seen some of this stuff prospecting around Arizona. Need to find some again and take a better look at the area. Quote Link to comment Share on other sites More sharing options...
Joe Z Posted July 5, 2015 Share Posted July 5, 2015 I just read Chris's Blog Very interesting on something i did not know and will be looking for Quote Link to comment Share on other sites More sharing options...
Hoser John Posted July 5, 2015 Share Posted July 5, 2015 Educate and prosper has always been the #1 rule of mining. Read in the winter when weather is bad and prosper in mining season from that knowledge...lotza luck--watch for contact points, fault zones and dikes also and you'll be a much happier miner. John 1 Quote Link to comment Share on other sites More sharing options...
Reno Chris Posted July 5, 2015 Share Posted July 5, 2015 Thanks for the kind words.Here is a link to the blog in question:http://www.minelab.com/usa/treasure-talk/a-tale-of-greenstone-goldNot every green colored stone is a "greenstone" - take a look at the photo in the article, it shows what greenstone really looks like.Yep, it does occur in Arizona and I have found gold in AZ in greenstone areas there.Dont forget the areas in schist or other rocks adjoining to the greenstone (meta-basalt) - many times the gold is actually coming from the adjoining schist. Its often the contact of greenstone and other rocks like schist that create the favorable geologic environment to form nuggets.For those interested in learning more about gold, gold deposits and how to find more for yourself, I have a lot of stuff like this in my book - Fists Full of Gold - and I know Bill has them in stock as I just sent him a batch. 4 Quote Link to comment Share on other sites More sharing options...
LowPoint Posted July 5, 2015 Author Share Posted July 5, 2015 Yep, you're dead-on about: "the contact of greenstone and other rocks like schist that create the favorable geologic environment to form nuggets." In this particular location, the greenstone was in contact with decomposed granite, and I have found this situation in more than one place (location) throughout this wash,...And, each location has produced nuggets in the past. In fact, the 6-nuggets pictured on my picture ID on this forum all are nuggets that I had found in these locations. Gary 1 Quote Link to comment Share on other sites More sharing options...
Uncle Ron Posted July 5, 2015 Share Posted July 5, 2015 (edited) I've found good gold in greenstone areas ... I'm attaching a 1/4 ozt nugget picture that actually has greenstone, red quartz, ironstone on the nugget ... The little gully where I found it has greenstone as the main bedrock ... The surrounding bedrock was iron schist... Cheers, Unc Edited July 5, 2015 by Uncle Ron 2 Quote Link to comment Share on other sites More sharing options...
Joe Z Posted July 5, 2015 Share Posted July 5, 2015 This post is getting better and better and gives me another angle to look for out in the AZ Desert. In Chris's right lower picture of the AZ Greenstone. The rock looks gray, does it have a greenish hue to it which i can't tell in the picture? Quote Link to comment Share on other sites More sharing options...
Reno Chris Posted July 5, 2015 Share Posted July 5, 2015 The rocks are green-gray, and a little more green than gray. Exact colors are hard to reproduce on line and depend a lot on the settings of your computer. 1 Quote Link to comment Share on other sites More sharing options...
Andyy Posted July 5, 2015 Share Posted July 5, 2015 Nice Gary. Thanks for posting this. I had forgotten all about that article, which I read months ago. At that time I did not really appreciate the clues of geology. Recently, I have been trying to get a better idea of what Greenstone looks like so I can keep a better eye out. Still trying to understand how to exactly identify a contact zone, but that should come in time. Quote Link to comment Share on other sites More sharing options...
Joe Z Posted July 5, 2015 Share Posted July 5, 2015 The rocks are green-gray, and a little more green than gray. Exact colors are hard to reproduce on line and depend a lot on the settings of your computer.Two Thumbs Up I do have your book which is also a big help but i feel dumb as a stump sometimes trying to figure it all out Thanx Quote Link to comment Share on other sites More sharing options...
Tortuga Posted July 6, 2015 Share Posted July 6, 2015 I've found good gold in greenstone areas ... I'm attaching a 1/4 ozt nugget picture that actually has greenstone, red quartz, ironstone on the nugget ... The little gully where I found it has greenstone as the main bedrock ... The surrounding bedrock was iron schist... Cheers, UncWow that's a real beauty!! Quote Link to comment Share on other sites More sharing options...
LowPoint Posted July 6, 2015 Author Share Posted July 6, 2015 Andyy,....A contact zone is where two (or more) different types of rocks had been (what appears to have been) melted side by side (due to extreme pressure and heat) such as a black schist and a white granite into one huge rock slab(or bedrock). The different rock-types is very obvious. I have also found the greenstone in contact with a very-hard creamy-white rock type. It doesn't appear to be granite, but is almost like a type of creamy white marble. The greenstone contact point with it was upstream with the majority of the (jagged) white creamy bedrock running downstream about 30-40 ft. which, it in turn made an additional-contact with some huge granite boulders. The nugget patch was all within the jagged white creamy rock.In some cases I have also found green sparkly-crystals on some of the flat-surfaces of greenstone, and on fragmented chunks(possibly quartz), which is a little lighter colored. I do find it interesting though, that in most-all locations of greenstone that I have run across, as long as there is a contact point of greenstone and another rock type I have always found nuggets,....But in the locations where there doesn't appear to be any contact point of greenstone and any other rock type the formation of gold nuggets did not occur. So, you cannot assume that just because you run across greenstone as a bedrock that there will be gold as well. ...Just Food for thought. Gary 1 Quote Link to comment Share on other sites More sharing options...
Andyy Posted July 6, 2015 Share Posted July 6, 2015 Thanks for the information Gary. I'm just trying to get a clear picture in my head since I have yet to run into a contact zone. But I know they are significant. Quote Link to comment Share on other sites More sharing options...
Swampstomper Al Posted July 7, 2015 Share Posted July 7, 2015 Here's North Carolina Greenstone and NC Greenstone in contact with Quartz..They're from about 70 mi ENE of Charlotte -- New London area: SA Quote Link to comment Share on other sites More sharing options...
Reno Chris Posted July 8, 2015 Share Posted July 8, 2015 Not every green colored stone is a "greenstone" - take a look at the photo in the article, it shows what greenstone really looks like.I kind of hesitate on these kind of discussions as too many prospectors just assume any green colored rock is what I am talking about - but its not. I always emphasize that greenstone is not just any old green colored rock. It is a metamorphosed basalt - a specific kind of rock - and is found with other metamorphic rocks. Sometimes in reports these rocks are referred to as meta-volcanics or just meta-basalt.Lots and lots of different kinds of rocks are green in color, but are not greenstone. These other rocks include rhyolites and andesites, as well as serpentine and soapstone to all sorts of sandstones and schists colored by chlorite, there are dozens and dozens of different rocks that are not greenstone but are green in color.Identifying rocks and minerals is a lot more than just seeing what color they are. In fact color is often the worst characteristic to use as there are many different rocks and minerals that are the same color.So Al - I am not really sure what kind of NC green colored rock you have, but at least in the photo, it doesnt look much like greenstone. Quote Link to comment Share on other sites More sharing options...
ShinyCy Posted July 8, 2015 Share Posted July 8, 2015 Reno Chris, I find this very interesting. My limited knowledge of gold producing areas in the western US is that they are more generally related to intrusive igneous minerals. However basalt is extrusive. For the metamorphism to occur, morphing the basalt into greenstone, must the basalt have been subducted? Then, in almost an intrusive manner, be thrust back to the surface? It seems like a very specific set of conditions which could really help to narrow down a search area. Quote Link to comment Share on other sites More sharing options...
Swampstomper Al Posted July 8, 2015 Share Posted July 8, 2015 (edited) "...I am not really sure what kind of NC green colored rock you have, but at least in the photo, it doesnt look much like greenstone."Here's a perfect example of why I love this forum, with me as the fall guy in this instance no less..!I of course take full responsibility for posting an incorrect photo along with making an incorrect statement.. For years I've been of the belief what I posted to be a sample of 'local' greenstone because someone (local to that area) who absolutely should know what's what told me it is.. When one sees the contact area in the next photo it's hard to argue against his statement.. All one need do is disregard the fact he's wrong and that's it -- game over.. There's no denying Chris is quite correct when he says there's more to geology than first meets the eye.. This is one of the reasons we all read his articles and columns: To learn, not to mention getting to travel along on his adventures.. I make no claim to knowing anything about geology beyond what I find in GA & NC streams, and even then I can't name what I'm holding in my hand for the most part.. I don't even qualify rank amateur status when it comes to knowledge of the field as far as I'm concerned.. With that said, I'll now post what " I " believe to be NC greenstone..No biggie -- if I'm incorrect I'm sure someone will let me know quickly enough.. Previous examples included in pix to verify I shot the photos: 10X magnification, different sample piece: I do wonder what the other rock is though, and if it's the same as what's in contact with the quartz..? SA Edited July 8, 2015 by Swampstomper Al 1 Quote Link to comment Share on other sites More sharing options...
LowPoint Posted July 8, 2015 Author Share Posted July 8, 2015 I may be stepping out on a limb a bit here, but I thought that I would provide a few photos of the greenstone that I was referring to in this, my post. It may be a bit hard to see the green in these photos, but the darker stone is actually more green than grey in color, and is a hard, smoothed basalt. These photos also reflect the contact zone between the greenstone and quartz. There is also some areas where a brownish color can be seen from the presence of iron oxide. Gary 2 Quote Link to comment Share on other sites More sharing options...
Tortuga Posted July 14, 2015 Share Posted July 14, 2015 (edited) Was at my usual spot in Arizona over the weekend and sure enough, that greenstone was EVERYWHERE. I knew I'd seen it somewhere before, just never paid any attention to it.Tons of quartz and schist rocks and boulders everywhere with thick veins of greenstone cutting right through it. There was even whole sections in the wash that were nothing but big greenstone intrusions. Pulled about an ounce of little pickers of rough, course gold out of this area this year with my SDC and GPZ.There's definitely truth to this geology. Edited July 14, 2015 by Tortuga Quote Link to comment Share on other sites More sharing options...
Joe Z Posted July 14, 2015 Share Posted July 14, 2015 Was at my usual spot in Arizona over the weekend and sure enough, that greenstone was EVERYWHERE. I knew I'd seen it somewhere before, just never paid any attention to it.Tons of quartz and schist rocks and boulders everywhere with thick veins of greenstone cutting right through it. There was even whole sections in the wash that were nothing but big greenstone intrusions. Pulled about an ounce of little pickers of rough, course gold out of this area this year with my SDC and GPZ.There's definitely truth to this geology.That's a nice sounding adventure. I wish you the best Quote Link to comment Share on other sites More sharing options...
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