# Surprising amount of black sand in NJ Pine Barrens pit



## Alondro (Feb 27, 2022)

On a whim after hearing about numerous spots around central NJ where people found black sand and gold flecks in streams and rivers, I decided to do a few pans near small streams and the outflow from an old sandpit within a few minutes walk of me, both of which have layers of strata composed of rounded pebbles and sand of mostly quartz from back in the ancient days when this part of NJ was all coastal sand dunes and surge zones. 

Sure enough, two pans in at the bottom of a hill where rainwater water had eroded tons of sand into a tiny trickle of a stream over decades, I hit the small alluvial fan with huge amounts of black sands, so much that I couldn't even properly pan it! I think I saw 2 little gold flakes, but there was so much heavy black sand (some is non-magnetic and I think it might be galena) it was hard to pick them out. So I just saved all the black sand and I'm drying it, then will use a magnet to pull out the hematite. That should reduce the volume a lot and make panning it down easier.

Anyway, an interesting find where one wouldn't usually expect. There are many such shore and dune gravel-rich areas that wash into the many streams and creeks in this part of NJ. Might as well check them! 

A picture of the drying black sands in the pan:


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## campbellj46 (Feb 27, 2022)

My in laws have a cabin in Taiwas Bay in Michigan. They think I'm nuts for panning the beaches  I have found gold in places, everyone swears, there isn't any. Maybe not a lot, but it's there. 

The prospector saying is true... "gold is where you find it". Good luck panning that spot in NJ. I hope you find the yellow metal. It's definitely worth a weekend or 2


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## jobinyt (Mar 13, 2022)

Wrap a magnet in plastic or such - leave the black sand wet and covered with water. Use the covered magnet to remove the magnetics.


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## Alondro (Mar 14, 2022)

jobinyt said:


> Wrap a magnet in plastic or such - leave the black sand wet and covered with water. Use the covered magnet to remove the magnetics.


Yep, that's what I've been doing. There's still a lot of black sand remaining that isn't magnetic. That could be broken fragments of a number of crystalline black minerals we have around the area to the north and west, where mica schists are plentiful and various combinations of zinc-iron, manganese and other metal sulfides and oxides can be found in crystal form. I have a nice bulk specimen of quartz shot through with large black crystals from Pennypack Park in north Philly. 

The veins are usually so small, you have to be right on top of them to find them. The geology is just so jumbled up in this region. Check out a state geology map of north NJ sometime! There's blotches and streaks of everything all mixed together. And that's just on the large scale map. Even more localized ones show a jigsaw puzzle of stuff, the result of this area being a continental plate and rifting zone multiple times before it finally settled down when the mid-Atlantic Ridge became the dominant geological factor hundreds of millions of year ago. 

I've long suspected, too, that there could be tellurides in patches up north. There are some small quartz veins I found 35 years ago as a kid on a specific mountain with suspicious granular 'pyrites' which don't tarnish and rust even after decades of exposure surrounded by black material and granules. It looks EXACTLY like pictures of tellurides I can find online, and after seeing pictures of hydrothermal quartz veins and confirming that indeed there was a basalt dike rich in potassium-iron feldspar (I got a piece broken off from a boulder and over the years sitting in the rain it has slowly turned to orange clay and released various tiny crystals and harder minerals) exposed on the north side of that mountain, it's my singular exploration goal this spring.

I think NJ has long been overlooked because everyone assumed it had already been thoroughly prospected. But that was long ago, and by companies looking for LARGE deposits. The little vein fragments wouldn't have been worth their time. But that's perfect for small-timers!


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## Deano (Mar 14, 2022)

When you have iron present in an ore it is worth putting a milled ore sample in 20% HCl, loosely capping the container and leaving it in the sunshine for warmth for several months.
Surprising how many samples will show gold flakes after this treatment even though fire assay on the original ore shows low or no gold values.

Deano


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## Alondro (Mar 18, 2022)

Deano said:


> When you have iron present in an ore it is worth putting a milled ore sample in 20% HCl, loosely capping the container and leaving it in the sunshine for warmth for several months.
> Surprising how many samples will show gold flakes after this treatment even though fire assay on the original ore shows low or no gold values.
> 
> Deano


Interesting. I have plenty of HCl, so I'll try that.


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## justprofessor49 (Mar 19, 2022)

I saw two people on my claim that had dug up about 4 gallons of black sand off of my claim. Having already assayed the sands, I didn't bother to tell them that what they had was a bucket full of finely divided manganese ore, but only chastised them for "claim jumping" and made them dump out their bucket of black sand.


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## Alondro (Mar 20, 2022)

justprofessor49 said:


> I saw two people on my claim that had dug up about 4 gallons of black sand off of my claim. Having already assayed the sands, I didn't bother to tell them that what they had was a bucket full of finely divided manganese ore, but only chastised them for "claim jumping" and made them dump out their bucket of black sand.


Oh boy! Manganese! *munches* ;D


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