# Look Dad, i found some gold ?



## necromancer (Jul 16, 2014)

today my 3 year old daughter & i are down by the river skipping rocks.

beside the river is a steep hill about 40 feet high, at the top of this hill they are doing a large construction project & have lined the top of the hill with a wall of loose rocks to keep things from falling down into the river system.

some of the rocks have rolled down the hill close to where we go to skip rocks.

to get on with the story, she brings me this rock that is shining all over one side with shiney veins running through it.

and says "Look Dad, i found some gold" when i seen it i was a little excited at the prospect of my 3 year old finding gold, i have never seen gold in it's natural form in my life, so we went over to where she found the rock and found more of the same type of rocks.

i really have no idea what this is, if it's gold or pyrite or both ? my first thought was that the people at the quarry must have seen this and had it checked out. but you just never know. here are some photos, not the best i may ad but photos none the less.

was wondering if there clear enough to see what my daughter had found, if not i could get better photos if i can find my camera.


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## necromancer (Jul 16, 2014)

3 more pictures










thank you for sharing your experience.


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## necromancer (Jul 16, 2014)

short video

https://www.youtube.com/watch?v=Yd2IVTXn7os&feature=youtu.be


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## cnbarr (Jul 16, 2014)

I looks to be mostly pyrite, but that doesn't mean there's no gold in it, one way to find out, assay!


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## Harold_V (Jul 17, 2014)

Pyrite is quite brittle, thus it will shatter if crushed. Remove a sample from the ore and try crushing with a light hammer blow, on a piece of steel. Gold will flatten. 

All of the pictures are rather fuzzy, so it's hard to tell what you have, but keep in mind, pyrite has a rather gray color when compared to gold. It has nowhere near the luster or golden color, which isn't obvious when you don't have both of them present at the same time. 

It's not uncommon to find rock with mica, often stained by iron, resembling gold. Can't tell if that's what you're seeing, but mica will crush, too, and, unlike pyrite, it's quite soft. 

Harold


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## g_axelsson (Jul 17, 2014)

You could...

Run your finger across the surface. Gold is malleable and when rock with solid gold is cracked the gold is teared and creates small spikes and sharp fragments protruding from the rock. Sulphides are fragile and fractures into rather flat surfaces. You can feel the difference.

Take a small fragment and crush it with flat pliers, mallable gold flattens while silicates and sulphides are crushed into many fragments.

Take a piece and draw a streak onto some unglazed china or a fuse. What is the color of the streak? Sulfides give streaks almost all dark / black. Silicates gives mostly white or very pale streaks.
Pyrite have black streak color while chalcopyrite have a black streak with a greenish tone.

Take a iron nail and try to make a grove in the surface. Pyrite is quite hard while chalcopyrite is soft as copper.

Use a multimeter and try to measure the resistance across a grain. Sulphides usually have resistances around 10-100 ohm, gold practically no resistance and silicates are good isolators.

... this is just a few of the different tests that can be made to discern between different minerals.

Göran


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## necromancer (Jul 17, 2014)

i checked it with my metal detector.

no beeps, i would think the metal detector would detect some amount of gold if it was gold.....


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## kjavanb123 (Jul 17, 2014)

My geologist friend used to say pyrits might contain gold, embeded in the structure, so assay would be better option. Also if you change the focus of your camera it will remove the fuzzyness from your photos.



Regards,
Kevin


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## g_axelsson (Jul 17, 2014)

A metal detector needs large continuous pieces of metal for it to react. Fine grains spread out in a rock would not give any reaction.

Yes, pyrite and other sulfides can contain a lot of gold locked in the matrix. The only way to detect it is to test. I've seen results of 2500 g/ton in samples of arsenopyrite and it was invisible to the eye. I've also seen grains of gold in pyrite where you could easily spot it... this one is in my collection.





Can you see the intensely yellow dots on the paler pyrite in the center of the picture? This ore is assayed at 3-5 g/ton and it is processed by gravimetric extraction and flotation of the sulphides.

Göran


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## necromancer (Jul 18, 2014)

that is very pretty !!

i have sent a sample to "cnbarr"
crossing my fingers


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