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So I have had this for years and decided to cut open, I have never seen something so hard and dense. Many people have question it and asked me to do some test. If any knowledge on what I can do to figure this stone out would be much appreciated.
I have done a magnet test and videoed it with pics. It draws magnet to it . From scale 1-5 , 5 meaning draws magnet hard, I would say a 3.
I have done the tile scretch test and it just scratches it with no mark left behind. It has different size and color spots in cutt and also has a lot of little sparkles on it. When wet you can see your reflection. I was hoping someone would know of anymore test I could do at home to help verify it. Thanks .




It will not let me load video. Sorry

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Im sorry i do not have a guess
That is a pretty specimen! :nerd_face::purple_heart::+1:

My thought is that you have a (granitic basalt) igneous rock. Most all of these groups show paramagnetism due to the iron, and manganese content.
BTW, it is the rock that is drawn to the magnet… but because of the mass of the rock, it appears the magnet is being drawn to the rock. I know it is an adjustment on words, but the premise of why must be explained.

Those bright reflective inclusions are most likely mica, which is often found in these types of rocks. Due to the pseudo-hexagonal shape, it may be more accurate to say that they are of the biotite mica group. But that is just my opinion.

Nice specimen. It no doubt has some weight to it?

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Thank you so much for info, I would like to learn about the stone to magnet or magnet to stone, I find it interesting it needs explained, anyway the weight fully emerged in water on scale weighed 1lb 10oz, and fully emerged but floating was 12oz. Agian thanks for your time and expertise.

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Chris, If you hang a nail from the string (like you did with the magnet), and hold it in front of your rock specimen; you will likely see that the nail is not attracted to the rock. This is because the rock doesn’t have a magnetic field.

In reasoning this out, it would then be logical to assume then that the magnet was not attracted to the rock, but vice-versa. That the rock did not move is simply a function of the disparate weight (mass) differences.

On a different note regarding mass… once when snowmobiling in Placerville, I jumped the plowed snow at the edge of a road (about 8 feet high) and crash landed in the middle of the road. I was slowly picking myself up when I heard the jake brakes on a logging truck about 150 yards away. I think only you here would know just how long it would have taken for a loaded truck would take to stop on a snowy road. That I am still here attests to the fact that I made it out in time.

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Thanks for explaining magnet concept, and in my opinion you got very lucky, not only because you were quick enough knowing you were moving slow but because the man behind the wheel of truck did right instead of panic. I have seen horrible happen with log trucks in my day and when you have 26 ton not stopping, it’s just a blink of an eye even at a 150 yards,.Glad u mad it and I am going to try the nail , just because u mintoned it, now I’m curious.

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I hope I can assist a bit… as there is some misinformation already provided. Your specimen is NOT basalt. First clue is that the iron element found in basalt is locked up mostly in ferro-magnesium silicate minerals such as pyroxene and they are not magnetic. Basalt rarely has a mica and when it has a little it is the pure black mica called “biotite” and not a gold round one that glitters as seen in your photograph. Micas have a platy crystal form (not spherical like in your photo). Further more basalt in not that dense, its specific gravity is about 3.0.

Since your specimen is magnetic… and has the round “golden” inclusion… and is very dense; I would guess that it is a man-made alloy. The gold spots look like immisibility droplets… the gold material can also be seen in the very fine “stringers” that run from one droplet to another. This is not a texture found in normal rocks or minerals. Many iron alloys can be magnetic and show immisicibility or exsolution features as they cool. I think the only way you are going to get some good information on this specimen is to consult with a “material scientist” who specialize in man-made materials… the good advice that is usually offered on this website is for natural gems and minerals.

Thank you so much and to hear example of what it could be is very nice, this is what we got back from a rock testing place, I’m still learning about elements and there means so I apologize I can’t really explain it but here they are for you to see. Thanks


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Great XRF readings. Most certainly a natural mafic rock. NOT a man-made product.

The outer rind has a different look than the inner (which looks to be a fine grained ferro-mag). Ask a mineralogist what they would call that.

Chris can this rock pick up even a pin? It’s certainly attracted to a magnet…but so is a nail, that does not mean they are magnetic.

Gabbro has the same mineral composition as basalt (olivine and pyroxene with smaller amounts of feldspar and mica). Gabbro is coarse grained while basalt is fine grained.

Your specimen appears to be finer grained and has a nice peppering of biotite.

So I tried picking nail up with stone, no such luck the only thing that will stick to it is a magnet, the more powerful magnet the quicker it goes to it. U think it’s a cool stone it has little blue crystals in it as well on the outer part of it. They are hard to find but once they are found they stand out. Sounds crazy but true. I will keep asking and testing . If you need anything else or have any ideas I would like to hear them. Thank you