Gold Ores

[UncleMatt]

The Infinium is not a good nuggetshooter to begin with. It can find medium nuggets (0.8-grams) up to 4" deep, but will walk over a half-gram picker at the same depth. Even the GPX 4000 used to walk over some smaller pieces with a DD coil, but the GPX 5000 can hear some really small stuff (.2-grams) with the right super fine settings. Many times you can pick up a seam with a detector because of the host rock, just depends.

Would you expect to find detectable host rock in situations where you have quartz seems with free gold in them? I guess as you said, that would all depend on what the host rock is, other than the quartz. I am just curious if anyone has had much luck hardrock prospecting with a metal detector to give them seam leads? In the San Juans you have a lot of polymetalic ores, so I am just going to have to see what I can find.

 

Amazon Forum Fav 👍

A History of Mining on the Kenai Peninsula, Alaska - Grab it through Amazon!

[TerryC]

The Tertiary gravels of the Sierra Nevada of California - Waldemar Lindgren, Frank Hall Knowlton - Google Books try this link.

Dave, here's something not so funny. A while back I purchased this book, volume 73 (not "paper" 73). I found it tedious and difficult to read. Now, I clicked on your link to find the paper was available FREE. I just learned the reason it was so difficult to read is I was not aware that the free version included the maps, illustrations, and photos that are not in the version I bought. I paid $ 99.00 for a lame digitized version! What a kick in the ass! Tnx for posting the proper product. TTC

 

[UncleMatt]

This is SUB GRAIN, and just posted on another gold forum I belong to. It was found with a Minelab GPX 5000 at 4".

Was those pickers found solo, or were they part of a posse?

 

[Terry Soloman]

Was those pickers found solo, or were they part of a posse?

All by its lonesome as far as I know, but I'm sure it has a cousin nearby..

 

[UncleMatt]

Not likely. Micro-gold in gold rich ore will not set off a metal detector. Flakes weighing .03-grams or more will read on several VLF machines like the GMT; Goldbug II; Lobo Super Trac

Hey Terry, my understanding is the Goldbug II is in the LF range though, not the VLF. Not that I care which frequency works the best mind you, I just need some input on the best LF or VLF machine to try to get seem leads with. I am not going to spend minelab money, but still want something good. Would that be the Goldbug II?

 

[UncleMatt]

Here is some confirming information on icmj.com's website in an article by Jim Straight of all people:

"Gold in Ore-Minerals

There are about twenty-seven telluride minerals. But, detectable gold is only found in three of them:

(1) Calaverite, a gold-telluride (AuTe2).

(2) Sylvanite, a gold-silver telluride (Au, Ag)Te2.

(3) Petzite, a silver-gold telluride (Ag, Au)Te2.

The gold-bearing tellurides, as either a primary ore or possibly associated with placer, are fine-grained and not a source for detectable gold. For gold to be detected it needs to be “free-milling” and of “detectable size” and not chemically “locked-up” within an ore-mineral as an accessory mineral. As an example, non-detectable gold can be found associated within a long list of other “ore-minerals” such as; antimony, arsenopyrite, chalcopyrite, fluorite, galena, pyrite, rhodochrosite, rhodonite, sphalerite, sylvanite, and tennantite."

However, here Jim states that calaverite and sylvanite both contain detectable levels of gold. If this is right, then I hope to be able to find just such seems with MD's in the San Juans.

 

[TerryC]

Here's another nice publication of the Rich Hill area. I recognize the cover as a hillside very close to Decision Corner. 4 authors include Chris Gholson. TTC