Unconventional diamond sources

The simple word for these ophiolite complexes is "serpentine". 

I have been doing some reading and field work on unconventional
diamond sources such as ophiolites. Can we start a new thread on
this? I’d like to discuss the idea that ophiolites and other
unconventional sources, even breccias and conglomerates from the
ocean floor may be future economic sources of diamonds. Refer to some
WWW material by W. Dan Hausel.

Peter, I accidentally deleted a post on micro-diamonds smaller than
1/10 mm (= 100 microns) as below “set” in plastic etc. Was that
yours? If so, could you please repost it or elaborate?

It was Nick Royall who posted a year ago that a 2 micron diamond
could be detected and tested with the proper equipment.

What I am looking for is a simple, low-cost method for assaying
micron-sized diamonds and even other precious stones in BC when they
are this small. A mm is 1,000 microns.

Why bother with stones this small? For the same reason prospectors
like Rock 9 follow vectors of low concentration flour gold up stream.
Hausel thinks the territory both I and Rock9 prospect has a lot of
diamond potential.

Hausel writes in gemstonebookstore.pbworks.com that although economic
finds have not yet been made, “diamonds have also been recovered from
a number of unconventional host rocks”. He refers to the Beni Bousera
ophiolite complex based on determination of “graphitized diamonds”
pointing to an astonishing 15% “primary diamonds”. I have no idea how
graphitized diamond is assayed but perhaps a geologist like John
Rasmussen can help us. I also have a practical reason for asking
because I am prospecting an area which the geological maps say is
graphite-rich and I have many samples of what appear to be small
graphite crystals. How would I know if they were once diamonds?

I was taken aback by the Nick Royall comment that “the simple word
for these ophioloite complexes is serpentine” but I recently got back
the petrographic report of a sample from a complex environment
related to what the geological maps call a “geological boundary”. It
is reported as “most closely related to a serpentinite”. Nearby there
are the graphite minerals and many of the rocks are ultramafic with
high concentrations of olivine and pyroxenes. There are also
breccia-conglomerate rocks across the fault line at this geological
boundary.

Perhaps Hausel is overly optimistic in his opinion that “North
America… could possibly become the world’s largest producer of
the gemstone” and since that is based on his UCD theory, the theory
warrants further critical (but fair) analysis. He calls it “a whole
new concept in exploration for diamonds worldwide”. Here are some of
the diamond-prospecting environments he refers to: “lahar, breccia,
conglomerate and even komatite” (Wawa, Ontario); “peridotite” (New
York and Maryland); “alkali basalts”; “organic rich ocean slab” (New
South Wales, Australia); “alpine peridotite” (Koryak Mountains and
Tibet); “breccia pipes” (BC and California).

Just as we often find diamonds in loose sediments on land, diamonds
could be located in loose sediments on the ocean floor, then
consolidated in breccias, conglomerates, mudstones, sandstones etc.
and moved… eventually into mountains and outcroppings on land.

If I am prospecting the the serpentinite-ophiolite rocks of a
terrane which has been pushed up scores of miles from the ocean floor
over a horizontal distance of hundreds or even thousands of miles, it
has had a most violent history of temperature and pressure extremes
starting in the upper mantle and lower crust. How different are such
forces from those which result in “as much as 1% diamond… by
weight” in iron meteorites (Hausel)? If you wash down a typical
roof-top as Nat Geo channel illustrated last night, you will find
sand grain sized particles of iron meteorites. Lucy in the sky with
diamonds?

What happens to a C atom as it makes its way over millions of years
from a location which may be near present day Japan to the present
west coast of North America? Could it not make the
diamond-graphite-diamond transformation a number of times? As we
learned from Jem Stansfield in the BBC video, a temperature of 2,500
with a blow torch for an overnight session is all that is needed to
make diamonds. Sudden impact or shifting of huge rock plates can
generate such a temperature.

What temperatures impacted my serpentinite-ophiolite rock through
hundreds of volcanic eruptions and earthquakes and perhaps even
meteorite strikes during its violent history?

Economic assaying for microdiamonds is a key factor in finding out
if Hausel’s UCD theory is valid or not. We need to know where the
microdiamonds are (and also the “burned out” former diamonds in
graphite) to establish field vectors and that takes hundreds or
thousands of assays. Mark Newton at Warwick U assayed Jem’s
torch-made diamonds using the “Raman effect”. The Raman frequency of
1332 is said to be definitive and according to
wiki/Raman_spectroscopy “The Raman effect occurs when light impinges
upon a molecule”. A single molecule? Nick Royall posted a year ago
that a diamond as small as 2 microns (1 micron = 1/1,000 mm) could be
hit with a light beam for diamond identification.

Also the sensitivity of the naked eye should not be underestimated.
I catch the intense glints of colour from my samples when the
lighting is right but I cannot see the outline of the crystals
causing the flashes of colour. Thus I asked Peter Rowe about his
experience with microdiamonds set in the plastic coating of jewelry.
How small can you go, is the question and it has both prospecting and
practical jewelry implications.

I can send 1 gram samples of pulverized stone to Acme assayers in
Vancouver and they will determine the ppb of scores of elements. My
guess is that they can do a Raman test with such a sample. The issue
is whether they can do it as affordably as they assay for gold,
platinum etc. Does anyone have any thoughts on whether robotic
assayers might work as well here as they will for large scale carving
of jewelry pieces? If a human being has to do Raman testing thousands
of times on a 1 gram sample, that is prohibitively expensive. If a
robot does it 24/7 without coffee breaks or sleep, it may be
affordable.

Thorough prospecting where geological maps show ultramafic
outcroppings in abundance, especially the west coast which Rock 9 and
I prospect on our respective sides of the border, would soon put
Hausel’s UCD theory to the test as long as we have access to
affordable assaying.

As with all your posts you expound on difficult theories but show us
no physical evidence and insist on collecting the spurious evidence
in completely the wrong way.

An elemental assay tells you very little about the rock and
certainly nothing about its diamond content.

Diamonds are not for ever, unlike the advertising claim, that is why
they are rarely found in other than a few host rocks and in certain
alluvial deposits. ;eft to their own devices they decompose in under
a billion years and dont take kindly to metamorphic diagenesis. That
is why you wont find them in serpentines. By the way, not all
ophiolite complexes are serpentine (they will be eventually) but I
used this word because the question was asking for a simple term.

QWhat happens to a C atom is well known as part of the carbon cycle
and has next to nothing to do with diamond prospecting. THis has been
pointed out before by more than one person but it doesnt seem to sink
in. The rocks mentioned are not diamondiferous because the term
"graphitised diamonds is meaningless-just graphite would have done.
Breccias have only once ever produced a diamond, same with ancient
conglomerates. Komatiites in Australia are a known host rock for
nickel but they are too old for diamonds, likewise the plutonic
deposits at Bon Accord Farm in SA. Your wildly enthusiastic
descriptions of the history of the rocks mentioned are so far from
being correct they make me wonder about where you are getting your
from.

It is not just heat or pressure alone that is required to make a
large diamond. Like ice that has a triple point of 0 deg C there are
fixed P&T curves that have to be followed to reach the correct
conditions. Diamonds may well be found in oceanic sediments but you
cant mine them. It would be like extracting gold from toenail
clippings, theoreticlly possible due to the concentration of gold in
the toenail but practically impossible.

As I said, show us your diamonds and produce them at a price of less
than the current methods and you have your economic assay result. The
sensitivity of the naked eye is useless at this scale. You cannot
determine them using an optical microscope but you can do many
things that will concentrate your sediment to make the chances of
spotting them a lot more likely if they are present. However, you
dont actually have a market for these diamonds as who wants to pay
for dust? The analogy for using microminerals with prospecting for
gold doesnt hold true. Gem diamonds dont wear out in rivers.

Nick Royall

However, you dont actually have a market for these diamonds as who
wants to pay for dust? The analogy for using microminerals with
prospecting for gold doesnt hold true. Gem diamonds dont wear out
in rivers. 

Thank you for your kind and considerate reply. Who wants to pay for
microdiamond assays? Oh, maybe De Beers. Establish a vector or other
“pointer” to a source maybe the source can be found - no matter how
small the diamond. That is the parallel to river gold.

The Hausel UCD theory (not exclusively his) merely gives the start
on reasons why UCDs may be found by prospectors. It is not a stupid
theory. You ask for my source. I gave the Hausel source and it is
online.

As you said elsewhere in this reply, there is no reason why diamonds
could not be found in sediments of the deep oceans (as plates move
apart from the effusive and eruptive volcanoes active there).

The peridotite and other mantle rocks which are deemed to be a
source of diamonds begin a dramatic metamorphic journey on the ocean
floor. Volcanic action is part of that history.

Serpentine is one metamorphosed result. But as we learned from “Jem”
and the BBC video, temperature is a sufficient condition to turn
graphite C into diamond C at 2500 degrees and according to

That T range is 1300 to 2700

And yes, those who talk about “graphitized diamonds” are saying
something not only stupid but simply false unless they have some
reason to think they were once diamond. But would they tell us how
they figured it out? One guess I had was that they had found
pin-POINT sized diamonds among the graphite crystals. But who knows
that assay technique?

In order to change graphite into cubic diamond structure, the
temperature/pressure applied has to change a flat hexagonal carbon
structure (similar in shape to the benzene ring) into a cubic
interlocking structure. The hexagons have to be flexed into a shape
which resembles a chair. Unfortunately, a U shaped structure is the
most common result of trying to change the graphite. This shape will
make a meta-cubic structure, but it does not have the proper
interlocking internal structure to make gem diamonds. Synthetic
diamonds use CVD and HTHP processes in the laboratory. Gem quality
diamonds just are not going to be produced by a blow torch, cubic
carbon crystals may be produced.

The placer gold emplacement analogy is quite correct. Some of the
largest Nambian diamond deposits are being mined at the ocean
shoreline, where dikes and pumping make access to the correct layers
available. However, these diamonds (some gem quality) were not
formed in the sedimentary environment. They have been weathered and
eroded from a metamorphic site upstream from the deposit.

John
http://rasmussengems.ganoksin.com/blogs/

Dear peter,

again your monologue uses the words “suppose that”… Another what
if and theorising on things that are just not that way in this
world. Again, show us the diamonds. You keep saying that all will be
revealed by analysis but you keep on quoting the wrong type of
analysis. I am not certain if this is avoiding the uncomfortable
argument to keep ones own theories alive.

Ophiolites are not metamorphic rocks but entire basic and ultrabasic
COMPLEXES that contain rocks that are known to be diamondiferous
when found in isolation so extrapolating this to masses is not
appropriate without understanding the formation of the particular
complex.

Your quoting of Leaming to describe a particular specimen again
cannot be extrapolated as you would wish. Metamorphism is not
aerobic, likewise the water contained in the rocks is not as separate
liquid molecules. The simplest answer to the diamonds being present
in amorphous carbon is that the carbon was originally there as a
diamond and the result is a retrograde mineralisation. hence the term
graphitised diamonds and not the other way round. Knowing more about
the other minerals present will tell you about the oxygen fugacity
of the rock as a melt and thus the chances of certain minerals
forming/occurring. metamorphism would not turn diaminds to graphite
but dissolve them and they would help form carbonates. The low
pressure forming of diamonds by burning dirty oxyacetylene limits
their size due to sublimation. This has been said before but you
still want it to show otherwise. You will never sell your field full
of mud as a diamond prospect and your amphibolite as jade so at
least be honest as to why you keep up with these postings and declare
the financial self-interest and lack of evidence to support your
claims. Searching the www finds all sorts of things but you must know
how to sort out the wheat from the chaff. No-one has taken up toenail
mining for gold yet so I reckon it is a pretty crap idea despite
assay results that are more promising than yours.

Nick Royall

Your quoting of Leaming to describe a particular specimen again
cannot be extrapolated as you would wish. 

I merely used his definition and pointed out its congruence with the
Xinjiang book.

What is your specific objection to Leaming’s definition of
(nephrite) jade as rock containing tremolite-actinolite in a
stone-strengthening pattern (variously called random, matted, askew
etc)?

diamonds just are not going to be produced by a blow torch, cubic
carbon crystals may be produced. 

Thank you for the reply. I am attempting to summarize the UCD theory
as it is presented in the literature and it would help if other
discussants would also give citations for their arguments. Hausel
provides a 100 page overview at gemstonebookstore.pbworks.com. He
calls it a “whole new concept in exploration for diamonds worldwide”.
But the nature of that new concept is only beginning to emerge. That
is why we are having this discussion.

I posted the Jem Stansfield BBC video on Orchid. He used a blow
torch and produced diamonds unless Dr Mark Newton at Warwick U was in
error about the Raman 1332 frequency and his declaration that Jem had
truly produced diamond. The grade and size of the diamond is not at
issue any more than the Discovery TV demonstration of blowing up a
barrel containing graphite which then became diamond. Mother Nature
has immeasurably greater resources and time to come up with bigger
and better stones.

When Nick Royall says “show us the diamonds”, I refer to examples as
above. If you also google “graphitized diamond” you can connect with
the Korsakov et al article from Journal of Petrology 2010 which
shows pictures of “graphite coatings around diamonds”. I found Figure
1 and Figure 6 (c) to be especially helpful. The latter,
interestingly is diamond within Mg-Ca which is within graphite. The
authors state that “carbonates could produce carbonate melts and this
could be very important for diamond formation”. Could the inner
diamond crystal then originate in an Mg-Ca carbonate?

Likewise the NR statements that “the term graphitized diamonds is
meaningless - just graphite would have done” and “metamorphism would
not turn diamonds to graphite” are not in accord with well
established science on UCD. I pointed that out by citing another
study of graphitized diamond previously. Korsakov is a second and
there are others.

The placer gold emplacement analogy is quite correct. 

All I was referring to with this analogy is that if you find
diamonds, no matter how small or in whatever host rocks, that is of
prospecting interest because it causes you to generate a theory about
their origin. Some of the microdiamonds in Korsakov et al are as
small as 25 microns (25/1,000 mm). I expect there were much smaller
ones as well but they were to difficult to analyze. If however one
finds 1 micron diamonds that will still be of great prospecting
interest. When I prospect for gold, if I find 2x earth crust average
at 5 ppb I wonder if higher grade ore is nearby. But ANY finding of
diamond, no matter how small, is of interest.

Some of the largest Nambian diamond deposits are being mined at the
ocean shoreline, where dikes and pumping make access to the correct
layers available. However, these diamonds (some gem quality) were
not formed in the sedimentary environment. They have been weathered
and eroded from a metamorphic site upstream from the deposit. 

I have never denied that where diamonds are found and where they are
formed are two different matters. Finding diamonds in some surprising
places is the UCD theory as I understand it. Then we speculate on how
they got there and over time try to turn the speculation into more
verifiable fact and theory. Korsakov et al in the Petrography section
refer to diamonds from “calc-silicate rocks(impure marbles and garnet
clinopyroxene) and gneisses”. Diamonds FOUND in marble and gneiss -
why not phyllite, schist, or even serpentinite and amphibolite?

There seems to be some difference of opinion in usage of the word
ophiolite. NR says “the simple word for these ophiolite complexes is
serpentine” and “ophiolites are not metamorphic rocks”. As I have
said many times, when cultures with very different histories in
mineralogy and gemology meet (eg Chinese and Western English) it
helps when we clarify how we are using words: wiki/Ophiolite says
ophiolite is “a section of the Earth’s oceanic crust and the
underlying upper mantle that has been uplifted and exposed above sea
level” and wiki/Serpentinite says “metamorphic transformation of
ultramafic rock from the Earth’s mantle”. A serpentinized ophiolite
would then be a metamorphic rock.

If the wiki definition is correct usage, then the ophiolite
originally is oceanic crust which could be a mix of sediments as well
as igneous and metamporphic rock AND the upcoming mantle rock which
we think is a likely origin of diamonds because of extremes of both
temperature and pressure.

But it may clarify the matter to talk about an ophiolite ENVIRONMENT
on its long journey to mountain formation on the surface, eg west
coast of North America. Diamonds originating in the mantle under
ultra-high pressure, ie UHPM conditions are partially replaced by
graphite (Korsakov et al cite four other reports to directly support
their findings on this). I am at a loss though to understand how
“metamorphism would not turn diamonds to graphite but dissolve them
and they would form carbonates” (NR). How does this transforming
(metamorphic) mechanism work as diamonds dissolve and how does the
solution become a carbonate? Maybe a few steps are needed to explain
this.

Whatever the transforming mechanism why should the graphitized
diamonds stay in one place? IMO this is the essence of UCD theory. In
prospecting we try to come up with some ideas on where the diamonds
in the diamond-graphite mix originated and whether it might point to
a nearby economic find. Hausel is clear that no economic find has yet
resulted.

***** If you have an ultramafic surface formation which originated in
the mantle and upper crust and it is now located in a complex
environment and you find graphite in that environment (perhaps in
phyllites, schists and calcite/dolomite/marbles), would you not want
to test the graphite for microdiamond nuclei regardless of the kind
of rock in which it is located? That is the practical prospecting
issue for myself, Rock9 and others. Your opinion is appreciated. *****

Humble graphite becomes a much more interesting mineral then as a
diamond indicator in UCD theory to validate Hausel as part of “a
whole new concept in diamond exploration worldwide”. The Aububon
Field Guide says graphite is found in “schists of regional
metamorphic rocks and in marble”. (page 350).

Show us YOUR diamonds in the claim you are trying to sell. Never
mind trying to spread the argument to all possible theories,
localities and situations. As I said before, you cannot use the same
prospecting methods and assumptions (except gravity separation in
stream sediments) as with gold because the deposition methods and
rates will be different. Ie: submicroscopic diamonds would not mean
big diamonds upstream/downstream and certainly analysis of clay size
particles will not show a great deal about the mechanics of the
deposition of the sediments. You also claim that the grade and size of
diamond are now not issues, yet this was the entire point of your
original posting more than 2 years ago. You cannot eat your cake and
have it as Shakespeare said. Likewise, he said that all that glisters
is not gold and when gold and diamonds are small enough there is no
glistening at all.

Gold is extracted chemically from concentrates and then melted to
form an ingot. This is not the extraction method for diamonds so 1
million 1 micron diamonds do not equal a one carat gem.

You are also wrong in the statement of reasons for why this thread
is here and active. It is purely you ignore what others have written
and continue to keep adding to the already tired topic with further
"supposes" and “what if’s” and misunderstandings about the
differences between the life cycle of an atom and a molecule or
mineral and the alteration of the latter.

I can find over 2 million refernces to proof of alien life on earth
and 190000 references to ophiolites and only a fraction of that with
reference to diamonds. Does that mean that aliens are 10 times more
likely to be living in yopur prospect because your use of
statistical methods indicate that it is.

I also wish that I had never mentioned ophiolites at all as this has
set you off on another giant web trawl that you now wish to share
with the rest of this JEWELLERY forum.

So, to recap:- you have no diamonds and you have no jade but you
wish to continue to convice the world that it is wrong about what it
should recognise as a gem. Have I missed anything?

Nick Royall

I merely used his definition and pointed out its congruence with
the Xinjiang book. 

There is nothing wrong with Leaming’s description of the nephrite
jade he found, what is wrong is that you try and ascribe this
inclusion of minor mineral phases to all rocks and then hope to call
them jade. It is like me saying that as I broke my arm falling out of
a tree when I was a child all broken arms are due to falling out of
trees and falling out of trees causes broken arms. Extrapolation of 1
data point doesnt work. In maths it is down to sets and subsets.

Nick