So I finally got around to looking more closely at the heavies from last years panning season. I was originally panning for gold but later discovered after some research that there's almost no gold in the area where I live. However, after even more research I discovered there are numerous known kimberlite and lamproite intrusions in the crust in my area. So I went to one of these locations with my gold pan and shovel and started digging and panning in a creek downstream. I should note that my panning skills aren't the best and I might have been too careful and leaving quartz in the pan.
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Pictures taken with a samsung s6 through a 15x loupe.
Thoughts and feedback are greatly appreciated!

Hello Frenchman:

Your pics show good indicator minerals...you're in the right spot for sure. What you're showing here is spot on for what you'd expect to see when prospecting near an eroded kimberlite pipe. A couple of the clear grains might be tiny diamonds but there is also some quartz in the pics. Don't get too hung up on clearing out all the quartz from your pan as you might very well discard a diamond or two in the process.

I'd keep collecting the heavies and run them at home, just like you're doing. From the coloration of the garnets, I'd say it is just a matter of time until you collect an unmistakable diamond crystal!

ASTROBLEME

Welcome to the forums Frenchman!

I hope to do a few panning trips this year for diamonds. Looks like you are on a trail already. Awesome! Keep at it.
There is tons of great information here. Thanks for sharing your finds with us.

Thanks for the replies! I can't wait for all the snow to melt away so I can go digging! Any tips on how to identify possible diamonds? I'm doing scratch tests on a tungsten carbide button bit used in blasthole drills with little luck. Are any of the thermal conductivity testers any good on rough stones? I realize identifying tiny irregular crystals are hard without proper equipment.

I've added some more pictures of bigger grains:
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I belive I found one! A teeny tiny one! Scratches tungsten carbide easily, leaves no powder and has characteristic diamond luster/shape as seen in the pictures below:
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I believe heat is another test... apply heat to it (boiling water or flame) and then touch it (or if you're really fancy, use a IR thermometer lol) and if it isn't hot, it's a diamond. If not, you'll burn your hand and be hesitant to do it again lol

Just boiled it in a glass of water in the microwave and put it straight into my mouth. At first I thought I lost it because I could not feel anything but then I realized it was just the same temperature as my mouth, which suggests excellent thermal conductivity. I'm afraid fire will damage it.

Cool! I live in the Fort and I've been pouring over geo maps scheming places to pan diamonds. bunch of diamond pipes west/northwest of town. I'm pretty new to panning in general but it's pretty much the same as gold?

Just like any heavy material, diamond will stay longer in a gold pan than lighter material. Keep in mind diamonds have a specifc gravity of about 3.5 which means it's about 3.5 times as heavy as water whereas gold is 19.2 times as heavy as water. This means loosing diamonds in the panning process is much more easy than loosing any gold if you're not careful.

Panning for diamonds is kind of misleading. It works by weight separation but not quite like gold panning. Take a look at https://www.youtube.com/watch?v=mEmRpGuVw5Y I know it for sapphires but the process is about the same for diamonds. This was at Gem Mountain in Montana. It demonstrates the same process taught at https://www.google.com/url?sa=t&rct=j&a...ZNFewAaLECYIRGw Crater of Diamonds State Park in Arkansas. The type of screen may vary but the process is about the same.

Leonard

Huh yea that is different, I would have treated it like gold and likely lost the good stuff.

I wonder if a gold sluice would work to concentrate the good stuff? Or is it too light for that design?

Maybe a really long gold sluice with low flow rate would do it but a gem sieve would probably be the best. A gold pan is great for prospecting for indicator minerals as it's fast and easy.

So I think I found a likely spot that is downstream of a pretty big diamond pipe, one that is claimed. The stream flows through a corner of forest service land downstream of the claim and the land is forest service land. So now I need to find out if anyone has Placer or other claims on that spot I'm scheming.

The geology of this area is pretty interesting, a gigantic ring dike structure from a massive granite intrusion, all kinds of stuff along the ring and it's shot through with Kimberlite pipes.

Astrobleme has you on the right poop. Those last pictures might possibly be a diamond. Try soaking it overnight in a plastic container with just enough Whink to cover it. Careful, that stuff contains hydroflouric acid and can be very dangerous if spilled or fumes inhaled. Get some at Walmart in the rust remover department. If it is a diamond, it will clean up and look better. If it is anything else, it will etch (frost) the surface. Hope that helps. I have panned many nice diamonds out of the creeks in your area, just be careful that you don't trespass. Most of the forest service roads accessing the creeks are locked. But nothing should stop you from walking in and trying. A bucket with classifiers, a saruca, and a shovel is all you need.