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Identity HelpExamine Rock Samples

13th Oct 2019 16:36 UTCMOREA TAVUL

I have found these collection of green, white and grey rocks in a river bed. Suspected that are diamonds and finally made home tests: heat,dot,scratch, mirror, flashlight, blacklight, lazer light, fog and water.

13th Oct 2019 18:58 UTCPaul Brandes Manager

I guess the first question is why do you believe they are diamonds? What were the results of any of those "tests"? The only test that is useful of those is what you call "scratch"; is this a hardness test or a streak colour test? With the photo provided and no other information, it will be impossible to give an identification. You may want to read the following post to help you (and us...):

15th Oct 2019 12:21 UTCMOREA TAVUL

I think they are diamonds because they do glow due to the sun light. Through the home tests; heated than fast cooling in water didnot break and scratch mirror and glass to check their hardness.Colour white and grey. Color of streaks white or grey.3Dimension. Crystal system isometric. Specific gravity of a piece 0.1g.Thanks.

19th Oct 2019 05:47 UTCMOREA TAVUL

Just today I have tested them by scratching against CORUNDUM WOOD working sandpaper they have proved me right. Awaiting your response.

19th Oct 2019 10:25 UTCThomas Lühr Expert

Sell them to De Beers !
(Sorry, i could not resist)

13th Oct 2019 23:12 UTCFrank K. Mazdab Manager

several of those "tests" sound very interesting. I'm particularly curious about the dot, mirror , flashlight and fog tests. I'm guessing the mirror test differentiates real diamonds from vampire diamonds (I presume vampire diamonds wouldn't see their reflections; however, their identities can be further confirmed with the garlic test).

oh, btw, that's a photo of a bunch of gravel. "Diamonds" appear to be our new "meteorites".

14th Oct 2019 01:34 UTCThomas Lühr Expert


19th Oct 2019 05:57 UTCMOREA TAVUL

Scratch test-through CORUNDUM WOOD working sandpaper they have proved me right. Awaiting your response

14th Oct 2019 00:41 UTCA. Mathauser

Scratch test - with corundum. Remember - the name of "diamond" comes from "adamas" - "invincible".

19th Oct 2019 05:37 UTCMOREA TAVUL

Scratch test-through CORUNDUM WOOD working sandpaper, are found in my country Papua New Guinea. Awaiting your response.

15th Oct 2019 16:20 UTCDonald B Peck Expert

Where are they from?

19th Oct 2019 04:30 UTCMOREA TAVUL

Found in my country Papua New Guinea suspected as diamonds and fine tested by scratching them against the CORUNDUM wood working sandpaper they passed the test.

19th Oct 2019 04:55 UTCBob Harman

I am not saying that what is shown are, or are not diamonds, but if even a significant % are true diamonds, the world would soon become awash with diamonds and we could all buy them as we now buy Herkimer "diamonds"!     CHEERS......BOB

19th Oct 2019 05:32 UTCMOREA TAVUL

Found in my country Papua New Guinea suspected as diamonds and fine tested by scratching them against CORUNDUM WOOD working sandpaper and they passed the test.

19th Oct 2019 05:51 UTCMOREA TAVUL

Please my CORUNDUM WOOD working sandpaper test was done successfully.

19th Oct 2019 09:10 UTCMOREA TAVUL

I have made the CORUNDUM WOOD working sandpaper test was performed successfully

19th Oct 2019 06:00 UTCFrank K. Mazdab Manager

So, I don't understand what you're looking for here.

No one here is going to tell you that a pile of gravel is a bunch of diamonds. Even if there was a one in a million chance that maybe one or two of those glassy chunks was actually a diamond, we wouldn't be able to identify that from a photo anyway; in essentially all cases, identifying a loose diamond requires an in-person examination from a qualified expert. But, if you've done all these other "tests" (most of which are meaningless) and from that have convinced yourself you've hit this outrageously rich diamond deposit, then why waste your time here?

Take your gravel to a gem dealer or jeweler and ask him how many millions of dollars he'll give you for it.  If he actually gives you any money for it, be thankful there are still people gullible enough to let themselves be taken advantage of (and I wouldn't recommend a second visit to the same dealer).  But if more likely he kicks you out laughing, don't say we didn't warn you.

19th Oct 2019 08:06 UTCKyle Bayliff

Lets try to remain polite... This forum is a place where non-experts can seek advice from more knowledgeable people.  If the original poster chooses to ignore expert opinion, that's on them, but we should try to maintain some level of professionalism.  Simply refrain from engaging with posters that do not want to listen if you feel that they are wasting your time rather than ridiculing them.  No, these are not diamonds.  That much is obvious to most of us, but may not be to someone who doesn't have any knowledge of the genuine material.

For the benefit of the original poster, should they choose to open themselves to other opinions than their own, sandpaper is not a suitable material to use for a hardness test.  If you scratch sandpaper, you may see some material come off, but this is just the grit coming off the paper.  This does not mean that your material is harder than the grit material.  To test hardness, you need to use a solid piece of the mineral you're testing against.  Additionally, for a streak test, typically unglazed porcelain is used, not glass from a mirror.  Diamond will not leave a streak on either, however, because it is harder than both porcelain and glass.  If your material did indeed leave a white or grey streak on the glass, then it is softer than the glass and most definitely not a diamond.

You state that the crystal system is isometric, but you do not state how you came to that conclusion.  The crystal symmetry of massive or cryptocrystalline material such as yours cannot be determined by sight alone as the crystal symmetry refers to the MICROSCOPIC arrangement of the atoms in the crystal lattice.  Powder XRD measurement or a similar laboratory technique is required to make that determination.

You stated that you think the material is diamond because it 'glows' in the sunlight.  I presume that you do no actually mean that it was giving off it's own light (even if that were so, this is not a property that a diamond would show).  Many minerals have a reflective or lustrous appearance that may make it seem like they are shining.  This is not sufficient to determine that your material is a diamond and not something else.

You also stated you think it is a diamond because it did not crack after being heated and rapidly cooled.  Many materials are resistant to thermal shock.  In fact, the process you describe is how glass is tempered.  Again, the ability to withstand rapid temperature changes is not unique to diamonds and not particularly useful for making identifications.

You stated that specific gravity of a piece of your material was 0.1 g.  These units are not correct for specific gravity.  Specific gravity is a measure of density, not mass, and is not measured in grams.  Additionally, the specific gravity of diamond is approximately 3.50 to 3.53, so the value is not consistent with diamond, either.

On the less quantitative side, before jumping to conclusions on any mineral identification, I would urge you to compare pictures of your samples to pictures of what you think it might be on mindat.  You should notice some significant differences in the appearance of your samples vs. the appearance of actual diamonds.

19th Oct 2019 10:32 UTCThomas Lühr Expert

You wasted your time, he is resistant :(

19th Oct 2019 11:12 UTCFrank K. Mazdab Manager

Hi Kyle,
I don't disagree in principle that of course we should remain polite. I don't feel I was especially impolite, but of course one's opinion of that will vary from person to person.

The poster posted the initial post close to a week ago, and in the interim numerous experts have chimed in on the improbability that his sample is diamond (letting along for the moment the fact that the geology of PNG is not conducive to diamond exploration). You wrote, "it may be obvious to experts but not to someone who doesn't have knowledge of the genuine material". That's fair. But after the poster was offered considerable insight about his samples over the last week, his knowledge didn't increase. Rather, he posted five of the exact photo... much like a lie told repeatedly often ends up finally being thought of as the truth, perhaps if we see this photo enough times we'll start to believe it.

Lots of people come here thinking they have diamonds, or gold, or meteorites, or other rare materials of high value and want us to help identify them (in the meteorite case, the post is typically deleted... no meteorite IDs allowed, and we really need to expand that policy to gold and diamonds). But nonetheless, many of these posters are sincere, and through discussions with the members here, typically leave their thread a day or two later probably a bit disappointed (because likely >99% of the time their discovery is less spectacular than they first hoped), but also leave more knowledgeable and probably in most cases appreciative of that new knowledge. But every once in a while we get someone that despite the experts' best explanations, just won't take no for an answer. A day or two of "no, I insist it's _____" is usually tolerated, but no after almost a week of this I'm frankly surprised this thread hasn't been closed yet.

And it's also interesting that when people ask us to ID a calcite, or a malachite, or galena, there's rarely any insistence that the experts must be wrong. One wonders why the situation is different for gold, diamonds and meteorites. Of course, we already know the answer. Again, while most people who request such IDs may genuinely want to learn what their sample is (even if harboring secret hopes that it's valuable), a small subset already *know* their sample is valuable. I honestly do find it perplexing why those people come here and ask "is this gold?" or "is this a diamond?" when in their minds they're already certain of the ID. Asking a poster that question might seem rude, but I'm curious about the answer nonetheless.

In any case, I think both you and I wasted too much time writing our respective posts on this thread. Your post is much more earnest than mine, and I applaud you for that. You clearly have more patience than I have.

19th Oct 2019 10:36 UTCJolyon Ralph Founder

No, these are not diamonds!
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