Everyone knows what gold looks like, but raw gold as it has formed in the natural environment is very different than gold that has been melted and refined.
This article will take a look at the different ways that you might find gold in nature, as well as some of the other minerals that you may encounter that can easily be mistaken for the real thing. If you are interested in prospecting for the precious metal, then you need to know what to look for!
Most of the gold that is mined around the world is found in lode sources, also known as hard rock deposits. This is where the gold is actually encased within rocks and must be manually removed from the Earth to extract the gold. The gold-bearing material is called ore.
Identifying gold-bearing ore just by visual inspection can be very difficult, or even impossible, depending on the concentration of the gold within the rock. Many ores that contain gold contain other metallic metals in them also, so there are likely to be a lot of shiny minerals mixed with the rock which may or may not be valuable.
The other challenge in visual inspecting gold ores for possible gold content is the fact that the total concentration of gold in a piece of ore is generally negligible. Most ores will have little or visible gold in them, so it requires further processing to actually find out if there is any gold in them.
Many of the large lode mining operations around the world are processing low-grade ores. As an example, some of the materials that they are mining only contain maybe the ¼ troy ounce of gold per ton of rock. So the actual amount of gold that is in a fist-sized rock is actually very little.
The purpose of mentioning this is to say that just judging a rock by how shiny it is really isn’t a very good indicator. Most gold-bearing ores found in nature are not shiny, and there are plenty of shiny rocks out there that contain no gold at all.
The types of materials that can be confused with gold vary widely. There are many different types of rock that are commonly confused with gold, but there are a few that cause a lot of problems for people that are new to gold prospecting.
Generally, it is silica, mica, and various forms of pyrite that are most common minerals found in nature that are confused with gold. These minerals can all have a goldish tint to them and are shiny in the sunlight.
Gold itself is generally not shiny, at least not reflectively. It is brilliant and golden, but its color does not vary in a different light. While minerals like pyrite will virtually disappear when you take them out of direct sunlight, gold is easily visible whether it is in the sun or not.
So understand that most of those shiny rocks are not gold. 99.9% of those shiny rocks do not really have any value most of the time.
However, on rare occasions, gold is visible in rock. These ores are generally considered “high grade.” Another term that the old-timers used for this type of ore are free-milling, which means that the gold could be extracted from the rock by crushing and panning, and did not require a chemical process to work them. It is often free-milling gold deposits that can successfully be hunted with metal detectors to find specimen gold.
Specimens of gold in quartz are quite rare, and depending on their beauty and “eye appeal” can be very valuable and highly collectible to mineral collectors, but there are a wide variety of specimens out there and not all of them bring a premium price.
Specimen gold is actually the vein of gold where it was running through quartz or some other host material that has broken off from the main source. (These can be indicators of a nearby lode source that can be mined, but sometimes they will be located miles away from the actual source, and have simply traveled over millions of years.)
Identifying this type of gold is a bit easier because unlike most ores the gold is exposed and visible to the eye. You can actually see the solid mass of gold rather than small specks of shiny “stuff.”
Speaking of quartz, let’s discuss the correlation between quartz and gold. Most people know that the two materials often run together, but they will use that as a reason to believe that the shiny rock that they just found is gold, simply because they found some quartz nearby.
Quartz is the second most abundant mineral on Earth. It comprises a significant percentage of the Earth’s crust, so simply finding some quartz and then assuming that there will be gold nearby is not very likely. There are thousands of quartz areas were no gold is present. Yes, sometimes gold and quartz are found together, but they are not dependent on each other.
Ok, so back to gold.
When gold is solid and in a large mass it is called a nugget. Gold nuggets are extremely rare, but they do exist and miners can still find them with hard work.
Gold nuggets come in many shapes and sizes. The majority of them are found in placer deposits, where they have accumulated within creeks and rivers. Millions of years tumbling around in the waterways generally make them relatively rounded and smooth. The average shape of a nugget will resemble a golden piece of chewed up bubble gum.
Not all gold is smooth though. Sometimes natural gold will still have very rough and interesting shapes. These would not actually be nuggets, but rather rough gold specimens. On rare occasions, these pieces will have crystalline formations.
Their rough shape is actually a result of having traveled and eroded less than most placer gold has.We’d all love to find a pile of gold nuggets, but the truth is that the VAST majority of gold out there is extremely small. Rather than big chunky nuggets, what you are more likely to find are small flakes, dust, and “flour” gold that is just tiny little specks.
Much like the various ones that we discussed earlier, those same shiny minerals are commonly confused with gold. Those shiny specks at the bottom of a gold pan have excited and disappointed thousands of prospectors for centuries. Remember, “All that glitters is NOT gold.”
Even on smaller specks, it isn’t too hard to tell the difference. Remember, gold in nature is always brilliant and doesn’t need to be in direct sunlight to look beautiful. However, most of the imposters will only be gold colored when they are in the sun.
If you are using a gold pan, it is also easy to see that the other minerals are not as heavy as gold. If you learn how to properly use a gold pan, you should be able to see the difference between how gold acts in your pan and how lighter minerals react when you swirl them around.
If you are reading this article, there is a good chance you found it by an internet search after finding a shiny rock that you think might be gold. If you just happened upon a rock while out on a hike or something like that, I hate to be the bearer of bad news, but…
Over the years we have easily received hundreds, perhaps even thousands of calls and emails from people who happened to find a shiny rock and want to know if it is gold. Sometimes they are still not sure, and sometimes people are all but certain that they have struck the “Mother Lode” and found a giant gold nugget. Then they email us a picture of a shiny rock that is clearly not gold.
That is the point of this article. Gold can look many different ways in nature, but it is important to know the difference between gold and the other minerals. Check out some of the pictures throughout our website of the various gold nuggets and gold specimens. Once you have seen a few pictures of real gold it is pretty easy to distinguish from the other stuff.
Gold is rare. Simply finding gold out in its natural environment is extremely challenging, even if you are looking for it. The likelihood of just stumbling across a big gold nugget while you are out walking around is unlikely.
Source: http://www.goldrushnuggets.com/whdogololiin.html