Diamonds? Options

[Frenchman]

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.









Pictures taken with a samsung s6 through a 15x loupe.
Thoughts and feedback are greatly appreciated!

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[Frenchman]

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: