Reno Chris 101 Report post Posted April 10, 2015 This is the type of gold on which the SDC 2300 and GPZ 7000 by Minelab do quite well. It's long been known that most PI detectors respond poorly on spongy and dispersed specimen gold. It is something like comparing a solid gold men's wedding band and a long fine link chain - both may be the same weight and alloy of gold, but the tiny chain responds poorly if at all, even when pushed into a mass, while the ring sounds off boldly at the same distance from the coil. The individual particle of gold are small and like the small chain links, that is what counts. Share this post Link to post Share on other sites
Geowizard 122 Report post Posted April 10, 2015 Rick, The SDC 2300 uses MPF (pulse) technology as well as the GPZ 7000 which uses ZVT (Bipolar pulse) technology. Pulse technology is good for "Horseshoes and Hand Grenades" as illustrated on the Minelab website. Best way to test the response is to check them out at a dealer if you have a chance! Verify the gold content by crushing, screening and panning. Then get the gold assayed or refined. Good luck! - Geowizard Share this post Link to post Share on other sites
Reno Chris 101 Report post Posted April 11, 2015 Pulse technology is good for "Horseshoes and Hand Grenades" Have you ever actually run a hand held PI metal detector by Minelab, Whites or Garrett? If so you would know that running them in a dealer's shop is quite difficult because of EMI from surrounding power lines. I think your statement shows a gross lack of knowledge about the subject. Share this post Link to post Share on other sites
Geowizard 122 Report post Posted April 11, 2015 You're saying they don't work in town and don't work in the field? - Geowizard Share this post Link to post Share on other sites
chickenminer 42 Report post Posted April 11, 2015 Rick, Dandy specimen! Hope you find a bunch more. Share this post Link to post Share on other sites
Jim Rattlesnake S 7 Report post Posted April 12, 2015 Nice specimen! Share this post Link to post Share on other sites
Rick N 3 Report post Posted April 12, 2015 Geo, 92% AU 6% silver, via xray. Share this post Link to post Share on other sites
Geowizard 122 Report post Posted April 13, 2015 Rick, X-Ray (XRF) measures only a small, approximately 1 centimeter "window". If your sample was pulverized into a uniform blend, then it's close - there's still a problem with "nugget effect" with XRF. XRF should be calibrated. There are companies that sell calibration standards for XRF. XRF is also prone to interference between metals. The response peaks overlap. - Geowizard Share this post Link to post Share on other sites
Rick N 3 Report post Posted April 13, 2015 Geo, it was a specimen sampling with enough exposed AU for the results I guess. Rough estimate. 30 power 10 power What is this material called? Share this post Link to post Share on other sites
Geowizard 122 Report post Posted April 13, 2015 Rick, Yes, I understand. Another feature of XRF is that x-rays don't penetrate gold and silver. The metals are too dense - just like lead is a shield for x-rays, From the results you have Gold and Silver! - Geowizard Share this post Link to post Share on other sites
Rick N 3 Report post Posted April 15, 2015 Thanks Chic and Jim. Enjoying the workout. I'm treating the work as a step through history, reliving the old miners hands on the pick and shovel. I do have some modern conveniences, Home Depot 5 gallon buckets. Hope to share more as I learn and continue to uncover the secrets. Share this post Link to post Share on other sites
Rick N 3 Report post Posted April 16, 2015 Chris, about your next article, I would be interested in the various formations, Calaveras, Mariposa, etc. In just our area, the formation changes in just a short distance. Also interested in the slip fault and fault systems. I just read an article (goldhunter.m.webs.com) talking about the different types of shoots, structural and chemical. I would love to know more about determining the difference. Share this post Link to post Share on other sites
Reno Chris 101 Report post Posted August 11, 2015 That's a fine idea - I'll do up an article on Rock formations of the Mother Lode country. Look for it in an issue of the ICMJ in the next few months. The formations change in a short distance going east-west, but run a long ways in a North-south direction. Its because the formations are compressed from a plate collision with the force coming in a westerly direction. Rick - any more gold coming from that spot? Share this post Link to post Share on other sites
Rick N 3 Report post Posted August 26, 2015 Chris, One from yesterday. 370.2g and SG test, as is normal for this mine, showes a negative value. Pockets in the quartz throw it off. The piece has good value running up through the stained area. Will crush and process to see results. I'll pm you some images of the system as it is becoming more revealed as I clean out the loose dirt and rocks. Share this post Link to post Share on other sites
Reno Chris 101 Report post Posted August 30, 2015 Any kind of air in the porous parts of the rock will throw off the readings quite a bit. The whole method of determining percent gold in quartz assumes pure gold and pure solid quartz. Anything else like air and it wont work. Share this post Link to post Share on other sites
Rick N 3 Report post Posted September 1, 2015 Chris, I've followed the old timer down the edge of the reef on the right and to the left he seemed to be working under that large rock as the seam twisted and diverted. Lots of action going on around this area. I think I need to follow the direction straight down. Thoughts? 353° strike and 48° dip. Share this post Link to post Share on other sites
Reno Chris 101 Report post Posted September 2, 2015 Its hard enough to read things in person - in a photo its much harder. The rock is weathered, and I've got a view of just a couple feet. There is no way I can look at that picture and tell you which way I would dig if I were there. Share this post Link to post Share on other sites
Rick N 3 Report post Posted September 5, 2015 Understood. Thanks. Share this post Link to post Share on other sites
Geowizard 122 Report post Posted September 5, 2015 Rick, The solution; Collect a sample of dirt and pan it. -Geowizard Share this post Link to post Share on other sites
Rick N 3 Report post Posted September 7, 2015 Geo, been sampling as I go. Will continue to do so. Just started on the boxworks on the hanging wall of the quartz seam. Will test sample. Decided to follow the seam on the surface and see what's what. Thanks. Share this post Link to post Share on other sites
Geowizard 122 Report post Posted September 8, 2015 Rick N, That's the way to go! - Geowizard Share this post Link to post Share on other sites
Reno Chris 101 Report post Posted September 9, 2015 Rick - look for that article on the rocks and formations of the Mother Lode in the next issue. Share this post Link to post Share on other sites
Geowizard 122 Report post Posted September 14, 2015 Rick N, You may be close to a significant discovery. - Geowizard Share this post Link to post Share on other sites
Reno Chris 101 Report post Posted September 15, 2015 You may be close to a significant discovery. If you know this, why not tell us how far away from that significant discovery he is, and in which direction. Share this post Link to post Share on other sites
Geowizard 122 Report post Posted September 15, 2015 Rick N has found gold. - Geowizard Share this post Link to post Share on other sites
