Jump to content

Help In Identifying This Rock


Recommended Posts

Well I was out today in a remote locating looking for nuggets with my 2300 and it sounded off on this rock. The area is noted for a lot silver. Not saying it is silver only my PI machine is pretty quiet unless it hits some kind of metal. It was lying on top the ground. It's dark gray to black. Maybe Hematite. Any one no for sure looking at a picture? Has some quarts in it also.

IMG_0269.jpg

IMG_0268.jpg

IMG_0270.jpg

IMG_0271.jpg

IMG_0272.jpg

  • Like 1
Link to comment
Share on other sites


Hi billdean… we’ve been finding naturally occurring native silver in northeastern Ontario for many years, but that experience doesn’t make it much easier to identify samples from other areas of the continent. That is because sample photographs are far less advantageous than having the actual sample in our hands to examine.

That the rock responds to a PI metal detector is a pretty good indication of native metal, but not necessarily conclusive. There are a couple of sulfides and at least four of the more common arsenides in our area that do respond with perfectly good “metallic” signals to PI units. Incidentally arsenopyrite does not respond to my PI units. I suggest that you run a quick, simple streak test on the suspect material to confirm whether it is indeed native metal or for example a white or silvery sulfide, or possibly galena.

Please determine the streak produced from one of the exposed occurrences in question. Select an area that protrudes from the surface. Rub it lightly across some white / beige porcelain tile or something similar from around the house that’ll give you a decent indication. For example, the bottoms of coffee mugs or French onion soup bowls are occasionally unglazed and will work just fine. Malleable silver produces a metallic silvery streak, whereas the brittle silvery sulfides generally produce dark streaks. None of them produce silver’s white metallic streak. There are other tests we can do to confirm silver, but the streak test is usually preferable because it is non-invasive. It won't damage your specimen.

Below are two small naturally occurring native silver examples that were field cleaned prior to the photos. Both exhibit silver nodules or horns protruding from the rock surface, which is fairly characteristic of  native silver in our area. Obviously a rock that has been subjected to the effects of erosion over eons of time will be characterized by a smooth or worn surface . But let’s hope the photos will be of some use to you as you examine your sample………………..Jim.

1068597064_0.7LBDENDRITICSPECIMENSFPAN18YYG.JPG.6e1a69ae5e754dc0fa6a69d0db170310.JPG

1419067425_2.5LBSILVERSAMPLEKERRSFPANDAR17YYG.JPG.3af7fd5f813294100fcf69942d135e64.JPG

  • Like 4
Link to comment
Share on other sites

Thanks Jim. I will try the streak test. The gold and mineral show is going on this weekend in Quartzsite. Maybe someone there my be able to help me also. I looked at it with a lope and it does seem to look like silver in places. Seems that there is at least 3 or4 deferent minerals in it. 

  • Like 2
Link to comment
Share on other sites

Dr. Erik Melchiorre will be at the Quartzsite Gold Show, and will be happy to analyze your sample with his XRF spectrometer.

  • Like 1
Link to comment
Share on other sites

Thanks Lunk.... I will look for him. I am starting to be more aware of all the gold ore sample rocks. I went to the place I asked you about. Got to be careful there or you could find yourself in the bottom of one of those deep mine holes. They were everywhere down that wash. 

  • Like 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...