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[Roger Warin]

Hi,
There are pretty Herkimer Quartz in Pakistan, Balochistan.
The specimens are very clear. They all contain polyphased inclusions included in negative cavities.
From the picture I think of a hydrocarbon inclusion with a droplet of water. What do you think ?
Roger.

[Pierre Joubert]

Hi Roger, it looks like a perfect negative crystal with fluid inside. I have some similar from the Steinkopf (Northern Cape) area. I could never get an adequate answer for the yellow fluid contents.

[lluis]

Hi, Roger, Pierre

All the ones of those that I have seen are labelled as "hydrocarbon" or "petroleum" included quartz.
Mine, bought around 10 years ago, was sold to me as "petroleum included quartz" from Balochistan.
All the ones I have seen fluoresce under UV. Mine also.
Done that water does not fluoresce, hydrocarbon or petroleum is what agrees with fluorescence seen... So, by fact, hydrocarbons (or petroleum)

Hope it serves

With best wishes

Lluís

P.D.: second time I sent this..... Hope that this time, well, surface.... :-(

[Roger Warin]

Thank you.
Indeed, hydrocarbon well fluoresces.
Roger.

[cascaillou]

Some of these crystals display 4-phases inclusions. The four phases were decribed in a GIA article as constituted of:
-yellow petroleum (oily flammable hydrocarbon), it shows bluish fluorescence under UV
-immiscible water (colorless)
-methane gaz bubble
-solid particles of black to dark brown asphaltite (generic term for bituminous hydrocarbons)

In some samples, both the bubble and the dark inclusions might be moving.

The 4-phases inclusions being trapped inside negative crystals and voids.

These crystals are indeed from Balochistan (Pakistan), the district of origin is uncertain, but most likely Zhob or Lasbela.

Those crystals are usually small (centimeter-sized), although te biggest specimens I've seen were 4 to 5cm in size.

As a side note, another type of quartz with interesting liquid inclusions are the ones from Bahia (Brazil) which feature bright blue liquid inclusions, constituted of an aqueous solution of copper sulfate.

[Don Lum]

Quartz cabochon with copper sulfate liquid inclusions and bubbles

[lluis]

Hi, Don

Inclusions may be of some copper salt, for blue, but by sure not a solution of copper sulfate in water... Blue is too dark for Cu2+ cation, unless it is a Cu2+ complex with an amino compound (say ammonia or an amine), which I think have only been found in Chile...

May anyone bring more explanations about those blue liquid inclusions in quartz?

With best wishes

Lluís

[Roger Warin]

Hi Cascaillou,
Thank you very much for that clarification.
I also observed some dark asphaltite phases.
However I do not think methane bubbles are compatible with a light hydrocarbon, because CH4 is soluble in it.

[cascaillou]

lluis, I was told it was constituted of a saturated aqueous solution of copper sulfate by a chemist who apparently had analyzed it. If saturated, such solution would indeed display a darker blue.

[lluis]

Hi, Don

I am also chemist....
I still doubt it is copper sulfate, for colour. Even if saturated, copper sulfate has a lighter colour. At least when I did copper sulfate crystallization, many, many years ago.
To my eyes, the colour could be the one of an amino complex of copper, but not so dark blue

Please, take a look at this video that shows how to crystallize copper sulfate...and take a look at colour of a saturated solution....



Other is copper amino complex colour....
Maybe this could illustrate it better

https://www.chemguide.co.uk/organicprops/amines/base.html
(link normalized by FMF)

With best wishes

Lluís

[lluis]

Hi, Cascaillou, Roger, List

Sorry, answer saying "don" should be addressed to you, Cascaillou

For Roger,.... Yes, methane is soluble in hydrocarbons, but if there is more than its solubility, still could be in the bubble...
No idea about if it is methane or not....No analyzed it, no have seen analysis, so....

With best wishes

Lluís

[Roger Warin]

Hi Lluis,
I do not think there's a problem of methane supersaturation.
In fact, the cavity is small enough not to allow displacement of the bubble, in particular because of the viscosity of the water.
All the cavities in these specimens have these 2 or 3 phases.
I am convinced that the bubble is filled with water, the solvent of silica in a hydrothermal medium. The slow and perfect crystallization of this quartz has forbidden any formation of impurity sails in this specimen.

Concerning the color aspect of the Don specimen, it could correspond to a partial complexation of Cu2+ by NH3.
The absorption spectra thus progressively shift towards blue-violet as a function of the number of coordinated NH3 molecules.
Most cupric salts, as CuSO4, dissolve readily in water and give [Cu(H2O)6]2+, but it is necessary to keep in mind that two of the water molecules are further from the Cu atom than the other four.
Anhydrous Cu2+ is colorless.
Addition of ligands as NH3 to such solutions leads to the formation of complexes by successive displacements of water molecules. The maximum of absorption shifts consequently. So, the maximum absorption is at ~ 800 nm for [Cu(H2O)6]2+ and for [Cu(NH3)4(H2O)2]2+ it is at ~ 600 nm.
Ammonia molecules have therefore exhaled the initial coloration of CuSO4 in water.
Without a spectrum, it’s no possible to conclude.

[lluis]

Hi, Roger

That water is needed for crystallization of quartz in such shape, and to allow inclusions, I have not the minimal doubt. That inclusion in completely filled, without a gas phase, is what I do not know. In photos, it looks as it is a gas bubble. But to think is not to know, so, maybe just water, hydrocarbon liquid and the black hydrocarbon phase... I do not know. For methane, I just placed what can happens, in case methane is there... (I suppose that a crystal should be smashed and then gas chromatography...)

For deep blue colour, yes, with ammonia one could get this deep colour. Is what I said saying an amino compound.... ammonia is also an amino compound...
But ammonia in nature, its compounds, are not exactly the most abundant ones.
Ammonia uses to come from organic compounds (normally dejections....). Being volatile, well, it uses to be displaced. To find it in a bubble inside quartz, sounds me as man-made. Just for difficulty in nature that this happen (how many sources of salmiac are there....? not too much, I fear. And not so many time ago were reported the first ammonia-copper compounds in Chile (that are not precisely abundant....)

Anyway, that is what I know from chemistry (career, interested in complex chemistry, and organic synthesis mainly), and what I know in minerals...

With best wishes

Lluís

[Roger Warin]

Hi Lluis,
I never said that this inclusion did not contain a gas, like He, but I did not see it. And my microscope is not a chromatograph. And since it is difficult to find a quartz without water ...
As for the amines, I know them well because in my youth I determined the structure of several amino acids and I also synthesized some as was customary at the time to confirm the analysis.
I do not think of amines of biotic origin to modify the color of cupric cations, but rather to "mineral" molecules like NH3 that could be present in hydrothermal waters. But this assumes that there is a complex. This could be only a concentrated copper sulphate, as Don believed.
Best regards
Roger.

[Don Lum]

I don't have a subscription to Gems and Gemology but here is a reference from a contributor from Barcelona to gemologyonline.com -> https://www.gemologyonline.com/Forum/phpBB2/viewtopic.php?f=20&t=20987 and I quote:

Elena Andia
Post subject: Blue fluid inclusions in quartzPostPosted: Wed Mar 04, 2015 5:23 pm
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Joined: Fri Feb 20, 2015 6:00 pm
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Location: Barcelona (Spain)
Hi to everybody!

During our last trip to Brazil, we bought some colorless stones with blue fluid inclusions. Few days ago we analyzed one of the stones. With the distant vision method it could be observed a refractive index of 1.55 approximately. With the microscope it can be seen typical inclusions from natural gemstones (crystal inclusions, two-phase inclusions, etc.) and two blue fluid inclusions. Under long wave UV radiation this specimen displayed a bluish green fluorescence.

We were investigating and we found an issue of Gems & Gemology that talks about quartz with blue fluid inclusions (probably a saturated copper sulfate solution). Here you have the reference:

John I. Koivula, "Colored fluid inclusions in quartz", Gems and Gemology, Volume 42, Spring 2006, pages 71-72.

We think it is a very curious gemstone and we hope you like it.

What do you think about it?

Cheers,

Don