Ore identification please help

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jdizzel07

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Feb 19, 2021
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I cant find any ores online similar to mine. Will somebody help me identify. #1 The grey looking ones look like silver. Very shiny. they also crumble when touched. #2 is what I believe to be gold and pyrite mixed. under magnification the gold color material is splattered like gold but has some crystals that have flat sides i assume that's pyrite. #3 looks like platinum or palladium I'm not sure. I will tell you what mine these came from after I get some responses. the mine is 140 years old I can say that much. Thanks for your reply's.
 

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Just my uneducated guess, it is hard to tell much from just seeing pictures, it looks like an iron rich ore, giving the rusty environmental oxidation on surface-exposed to the surface over time, the rock also may be loaded with pyrite one of the many types of iron ore.

a little study in rock type identification can help narrow down your search, hardness, luster, crystalization, acid tests, and so on can help you identify different rock types, many times these will also give clues to which metals or metallic-mineral salts or gangue materials the rock may possibly be composed of, and other such information as if it may contain arsenic, sulfur, or selenium or so on.

Assay's (there are several types and many times you may need more than one type, the assay can tell you much more, not only what values it may contain, but also give you information of processing and the dangers which will be involved, as well as possibly giving you clue to processing if needed, or at least enough information to find out how other mining operations in your area are processing the ore, are they crushing it for road gravel or mining it for gold...
 
I cant find any ores online similar to mine. Will somebody help me identify. #1 The grey looking ones look like silver. Very shiny. they also crumble when touched. #2 is what I believe to be gold and pyrite mixed. under magnification the gold color material is splattered like gold but has some crystals that have flat sides i assume that's pyrite. #3 looks like platinum or palladium I'm not sure. I will tell you what mine these came from after I get some responses. the mine is 140 years old I can say that much. Thanks for your reply's.
Most of the time gold comes with pyrite, those shiny points are pyrite. If there's quartzs veins too, there must be gold in it. I suggest stannous chloride test as it's fast and reliable.
 
Pic 1 looks like a bunch of mica, pics 2 and 3 are definitely pyrite or chalcopyrite, more likely the former since chalco tends to get colorful over time. I doubt theres any gold worth recovering in there but if you want to be sure crush some of it up, roast it to drive off sulphides and other volatiles, and either pan it out or do a fire assay.
 
Most of the time gold comes with pyrite, those shiny points are pyrite. If there's quartzs veins too, there must be gold in it. I suggest stannous chloride test as it's fast and reliable.
depends on geology and the location in the world. region of Carpathian mountains (europe), where i live, have numerous pyrite/quartz outcroppings, but no gold involved most of the times :) it is a good lead, gold like the sulfur, arsenic and antimony...however not every time :)
 
What do you think about quartz and limonite porous basic ore? I've found these samples in a volcanic area near 3 faults.
 

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Of the first three photos posted; Photo #2 is a possible option for silver, photo #3 is a decent option for gold and possibly silver too.
 
Unless you can see visible gold, you cant just look at a rock and know its ore. If that were possible, there would be no need for assays - but miners have been doing assays for many centuries. You can crush up a couple pounds and carefully pan the material to see if there is any gold, and that is a rough and approximate test that can be done at home. If there is little or no gold on the panning test, its not good ore. Quartz is the most common mineral on Earth, being made of the 2 most common elements in the Earth's crust. Its important to remember that there are HUGE amounts of quartz with little or no gold. Finding some chunks of quartz is meaningless. If it has good gold, then that is another thing, but rich gold quartz is quite rare. This is the type of stuff you want to find.
 

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Unless you can see visible gold, you cant just look at a rock and know its ore. If that were possible, there would be no need for assays - but miners have been doing assays for many centuries. You can crush up a couple pounds and carefully pan the material to see if there is any gold, and that is a rough and approximate test that can be done at home. If there is little or no gold on the panning test, its not good ore. Quartz is the most common mineral on Earth, being made of the 2 most common elements in the Earth's crust. Its important to remember that there are HUGE amounts of quartz with little or no gold. Finding some chunks of quartz is meaningless. If it has good gold, then that is another thing, but rich gold quartz is quite rare. This is the type of stuff you want to find.
Very nicely said. Majority of gold comes with quartz, majority of quartz comes without single flake of gold :) So many people find a glittering rock and firstly think it is something extremely valuable. Most of the times, it´s mica or oxidized pyrite. Refusing to take an advice and do the assay, they jump straight to the acid tests and unconclusive messing up etc...

For me, first test is to crush and pan. If I find the gold, perfect. If I don´t, in my situation there is no way to proces any reasonable ammount of sulfidic ore rich in silver/gold. So, big sad... Life goes on :)

Somebody may be interested also in the bulk processing of rich ore with invisible gold, but as you say, without proper analysis, it is all just guessing. Like many times here on the forum, assuming if some 4 glittery-like pixels on the photo are gold or pyrite/mica in some casual-looking rock :D and so many being totally certain about their guess to be the truth without any other proof.

Good specimens
 
Unless you can see visible gold, you cant just look at a rock and know its ore. If that were possible, there would be no need for assays -
The first three photos by jdizzel07 are the photos that I was commenting on.

If you can not identify metal rich mineralized rock that may contain precious metals, as well as what precious metals the rock may contain, then you have much to learn.

I know that I can.

The many samples of mineralized rock (ores) sent to me for an assay that I speculated contained gold or silver, and did; as well as the ores that I have found speculating the same have proven such to myself and to those that I have been of service to.

For me, it's no longer does the sample in question contain gold or silver; the question is how much does it contain, and a fire assay will determine that.
 
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Assay, assay, assay. Some of the biggest deposits currently mined, have no visible gold. Some of the richest mines in our area are what appear to be a clay gouge seem in a fault. They actually are composed of mainly a calcium gangue, and brecciate pieces from the wall rock. Crushing to - 200 mesh and panning reveals no visible gold. The stuff fire assays at around 20 OZ/Ton. You will never know till you do a proper assay. Mixed among this seam are the occasional nugget.
 
Assay, assay, assay. Some of the biggest deposits currently mined, have no visible gold. Some of the richest mines in our area are what appear to be a clay gouge seem in a fault. They actually are composed of mainly a calcium gangue, and brecciate pieces from the wall rock. Crushing to - 200 mesh and panning reveals no visible gold. The stuff fire assays at around 20 OZ/Ton. You will never know till you do a proper assay. Mixed among this seam are the occasional nugget.
Nicely stated and point made. Not all valuable ores will pan.
 
If you can not identify metal rich mineralized rock that may contain precious metals, as well as what precious metals the rock may contain, then you have much to learn.

Its so wonderful to have found someone as knowledgeable as you are! Just to confirm your extensive expertise, I have attached 10 pictures of some rock. Can you well me which of these have significant gold? I actually know about all 10, so I know the correct answers from testing and assaying, but I am sure you will get 100% correct! Please let us know your determinations. Just a hint, there is no visible gold in any of them, though some are very rich in gold.
 

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Sample #1. The samples of hematite enriched material similar to this that I have assayer has never been any less than 1/5 of an oz per ton gold.

#'s 6, 7 & 10 are my other choices for most likely material.

Sample #7 would be suspect for silver and possibly pgm's.

#'s 2, 3 & 5 would be secondary choices with expectations of silver being dominant.

There, I answered your retort.
Let's see how I scored.
 
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Sample #1. The samples of hematite enriched material similar to this that I have assayer has never been any less than 1/5 of an oz per ton gold.

#'s 6, 7 & 10 are my other choices for most likely material.

Sample #7 would be suspect for silver and possibly pgm's.

#'s 2, 3 & 5 would be secondary choices with expectations of silver being dominant.

There, I answered your retort.
Let's see how I scored.
My experience with hematite here is anywhere I found the nice iron ore like #1, it contain no gold. Not saying that hematite ore do not have gold anywhere in the world. But here, I do not know of any that do.
And our country has mining history of over 3000 years. Just no hematite type ore. Strange for many, but it is what it is. Numerous quartz hydrothermal outcroppings here, volcanic breccia stuff, supergene gold, mustard gold, strange gold-copper alloys in perm type rocks (wild to hear, just recently found), gold-nickel alloys of mustard gold, sulfidic ores of nearly any kind, gold in carbonates, barite, associated with uranium and rare earth minerals (this is a quite rich deposit, yet very small), flysch paleoplacer deposits, porphyry deposit with more than 40 tons of gold suitable for open pit/cyanide... But no obvious gold-hematite association known to me.

Of course, you can do "educated guess" on any rock you find. Question is if you want to extrapolate few known examples to whole array of different samples from different regions.
 
Assay, assay, assay. Some of the biggest deposits currently mined, have no visible gold. Some of the richest mines in our area are what appear to be a clay gouge seem in a fault. They actually are composed of mainly a calcium gangue, and brecciate pieces from the wall rock. Crushing to - 200 mesh and panning reveals no visible gold. The stuff fire assays at around 20 OZ/Ton. You will never know till you do a proper assay. Mixed among this seam are the occasional nugget.
Similarly bizzare deposit was once mined here. Supergene gold, surface mining no deeper than 30-40 m. Hydrothermally altered andesite with numerous faults, cracks and dislocations filled with clay material or manganese dioxide rich black "mud" :D Host rock was sterile for gold, yet containing so much pyrite and sulfides.
Samples of this manganese dioxide muddy "ore" assayed from 10-100g/ton gold and similar silver. Gold particles were on the borderline of visibility. Significant fraction under 0,1 mm. Sticky, water repelling thick heavy mud.
Simultaneously, in some cracks, there were very nice quartz crystals, which were than covered with gold rich fluids and some very nice specimens are found with weathered pyrite/tetradymite crystals on the top of small quartz points with occasional small flakes of gold. But these were rare.
It is unknown to this date how miners in 13-16th century were able to recover the contained gold.
 
Unless you can see visible gold, you cant just look at a rock and know its ore. If that were possible, there would be no need for assays
Well said Chis (& nice specimens by the way)

Back in the late 70s early 80s when I lived in Northern California (Salmon River district of the Klamath/Trinity National Forest) there were two hard rock miners (LOTS of placer miners)

One of the hard rock miners held the paper on an old hard rock claim that was about a half mile hike down to the old cabin & tunnel - the tunnel of course had caved in but outside the tunnel was a pile of ore

I spent a winter snowed in & living in the old cabin (had to hike about 3 miles down the mountain to Franks place if/when I needed to go to town

Anyway - to make a long story short - that pile of ore - you could break rocks all day long & look at them with a loop & never see so much as a speck of gold - however that ore assayed at around 4 ozt/ton (plus/minus depending on sample)

That summer (after spending the winter snowed in at the cabin) I packed that pile of ore out with my horses & mules - hauled it down to the mill site & ran it - figure it was like 10 -12 tons

It was the assays that told us it was worth packing the ore out

Edit to add; - top two pics are standing on the logging road where the trail down to the cabin is/was

Kurt
 
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