So I busted the rock a little more and put the crystals that fell out under the microscope. I thought this piece was pretty cool. Sorry for the poor quality. It's a reworked video snapshot. It was the best way to capture the changing shapes on the surface while moving the light around to change the angles.
I see a rock made of stacked triangles. Both strait edge and curved edged triangles, also squares and 'diamonds'. triangles upon triangles upon triangles. Sure wish I could get better image quality. It's not much more than a speck of sand.
Mayhap JiminIdaho will chime in as this is something of a specialty for him. Looks like a good candidate to me. Thoughts are peridotite, garnet for sure but the clear and blues I'm not sure about. Appreciate the effort with the magnification
LOL...I was also waiting on others. I'm not sure. My gut says 'No'. kimberlite tends to be monolithic. It doesn't have 'pockets' of other rocks. If you look at the samples, you can see places where there are breccia pockets that were absorbed by the base rock. I've never seen kimberlite with those pockets. Is it similar to kimberlite?..sure. Kimberlite is more of a pure mass, embedded with crystals of garnet, chrome diopside, pyroxene, etc. But keep in mind, I'm a hobbyist, like you guys, not an expert. In any case, it's a great specimen.
Jim
Haha I'm not sure either but it sure reminds me of a garnet Xenocryst which are found in kimberlite, I think... The pocket with the garnet? might be the Xenocryst. The rest of the rock looks like it def could be kimberlite to me and the fact it seems to have a xenochryst makes me think you might have kimberlite. I hope someone else chimes in too as I'm not an expert. Nice find.
The green looks like what DDancer said. Where did the rock come from?
At first I thought water worn basalt but it also looks like a cemented conglomerate mass.
The peridot might have moved me to basalt.
I recall reading that up untill they found lamprolite they believed only kimberlite hosted diamonds. I did also read about micro diamonds being found in subducted and relifted sea floor material in scandenavia. As bold as it is, I propose that perhaps other sources than those known could host similar materials. After all the ring of fire here in the PNW is supposedly subducted and prone to explosive volcanic events. Diamonds have been found, but no source located. So I suppose technically it wouldnt be kiimberlite would it. I generally espouse the "If it walks like a duck and it talks like a duck, maybe it tastes like a duck" theory.
At any rate when I am able to make the trip I will do a complete reconisance of the area and collect proper samples. Let us see how this duck tastes.
It's actually a theory that my brother and I had been kicking around for a little while now, so this material really got us excited. Why are there diamonds with no source located? Well maybe the souce is completely ground away, but maybe, just maybe, it is not the same as it is in other places? It's just a theory mind you. I have been proven wrong before....... but not very often ,LOL!
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My friend just sent pics of the material they are quarrying by her place. It is not the same material as the sample she gave me. I suppose you married guys might know what it's like having a woman who is just collecting pretty rocks while you are searching for valuable minerals, lol.
As for me I just want to get in a creek down grade of the source and see what is sitting on my screens after a little shaking.
I'd sure check the area. There are many reasons for diamonds being on the surface. A relatively shallow volcano could bring the odd diamond up. Or, as you mentioned, they could be raised in a subduction zone. Kimberlite, or not, that is a very interesting specimen, and deserves more research.
Jim
I steered away from basalt as the sample does not show enough uniformity I see in most basalts. For some reason I dont expect north american kimberlite to be like south african but I'm a novice when it comes to that material.... prefer to look for zeolites and sulfur/sulfide minerals in volcanics Does not fit my thoughts on a conglomerate or a compacted ash but again~ novice. Should be some interesting stuff in that area though and hopefully some bigger gemmy stuff if no diamond shows up.
Jim I look to your knowledge in the field here as you've often suprised me with your insights in this area. Hehh. hvacker makes a good point as well and is another member I look to for insights
Ditto, DD. I've always felt you're more knowledgeable than I am. I'm just an old rockhound that's done considerable work in diamond prospecting. When I posted, I hadn't noticed you were the author of #3. HV is also really sharp on this stuff. That particular rock is tough. Obviously igneous. When I look at pics of kimberlite, however, I don't see many that have different-colored background material. But, even if it's not kimberlite, it's a great sample for diamond prospectors to use as a reference for what they're looking for. Another thing just occurred to me also.....From my readings,. kimberlite breaks down as it is exposed to air, sun, and weather. That specimen looks like it has been weathered for a considerable period of time.....it's somewhat rounded and polished.
Jim
Just my two cents but it does not look like any Kimberlite I have seen! However, it does have an appearance of or at the least, a resemblance to Lamproite.