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#1 2013-08-18 12:24:57

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 5,427
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Glass

I don't where to put this, so I'll put it here.

Watching the 2013 Mars Society Convention via Livestream. The manager of the JPL rover project said Spirit found a deposit of 91% pure silica. They named it Silica Valley. At the Mars Society Convention in Chicago, I presented a paper to smelt aluminum on Mars. Ore is bytownite; orbiters found 21% to 27% bytownite in normal Mars soil. One by-product would be silica gel. That could be processed to make glass. However, a much simpler process is to melt white silica sand.

Either way, you need to add soda and lime. That is sodium oxide, and calcium oxide. Normally, these are added as limestone, so sodium is in the form of sodium carbonate (calcite), but when dissolved in molten glass the heat breaks down sodium carbonate into sodium oxide and CO2 gas. The melt has to sit for a while to off-gas. Glass also has some aluminum and potassium, and a touch of iron and titanium; all oxides. Glass for bottles and jars also has magnesium oxide. These are all found in basalt, so it means adding regular sand, not just pure white silica sand. But again, starting with silica sand is a lot easier than a smelting by-product.

A couple articles on the "Silica Valley". It's actually a small deposit, not a valley.
2007: Mars Rover Spirit Unearths Surprise Evidence of Wetter Past
and
2011: Mars Exploration Rovers Update: NASA Ends Spirit Mission

Last edited by RobertDyck (2013-08-20 19:44:35)

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#2 2013-08-20 09:27:48

GW Johnson
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From: McGregor, Texas USA
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Posts: 3,148
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Re: Glass

Sounds to me like glass might be fairly easy to make in certain locations on Mars.  All one needs is an appropriate furnace for the melt.  The rest should be like here,  except maybe the casting and solidification.  The cooling rate might need to be retarded at Martian conditions,  to keep the glass from cracking or turning back to crystalline (sand or chunks) form.  We cool it fairly slowly here to keep it in the amorphous state that is glass.

This does apply only to locations where SiO2 sand is actually available,  though. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#3 2013-08-20 15:56:15

louis
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From: UK
Registered: 2008-03-24
Posts: 3,715

Re: Glass

Isn't calcium in rather short supply?


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#4 2013-08-20 20:07:59

RobertDyck
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From: Winnipeg, Canada
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Posts: 5,427
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Re: Glass

Sojourner soil samples (not rocks) contained 5.5% - 6.4% CaO. Opportunity is the energizer bunny, it kept going, and going, and going. But the first published soil samples (again not rocks) contained 5.15% - 6.94% CaO. This is from the APXS instrument on both rovers. Window glass consists of 9% CaO, bottle/jar glass 10.5%. So it does require finding a mineral with concentrated calcium. Calcite would be idea; results from orbiters claimed it was there, but rovers have had difficulty finding it. You could use anorthite (feldspar), augite, dolomite, or gypsum. Albite could be a source of sodium, and plagioclase feldspar is typically a mixture of the two. You could use feldspar that has a little microcline, which has K as well as Al and Si. But you would want to avoid anything with crandallite or chlorapatite, because they contain phosphate.

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#5 2013-08-21 16:21:59

louis
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From: UK
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Posts: 3,715

Re: Glass

RobertDyck wrote:

Sojourner soil samples (not rocks) contained 5.5% - 6.4% CaO. Opportunity is the energizer bunny, it kept going, and going, and going. But the first published soil samples (again not rocks) contained 5.15% - 6.94% CaO. This is from the APXS instrument on both rovers. Window glass consists of 9% CaO, bottle/jar glass 10.5%. So it does require finding a mineral with concentrated calcium. Calcite would be idea; results from orbiters claimed it was there, but rovers have had difficulty finding it. You could use anorthite (feldspar), augite, dolomite, or gypsum. Albite could be a source of sodium, and plagioclase feldspar is typically a mixture of the two. You could use feldspar that has a little microcline, which has K as well as Al and Si. But you would want to avoid anything with crandallite or chlorapatite, because they contain phosphate.

Thanks for the update. Sounds like a higher proportion than first thought.

I have long thought that if it could be done, then glass would be an excellent material for use on Mars within the habitats. Scaled down, automated glass making machines could be delivered to the surface for use by the first colonists.


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#6 2013-08-21 21:35:13

SpaceNut
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#7 2013-08-22 08:29:59

GW Johnson
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From: McGregor, Texas USA
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Re: Glass

Spacenut's link to the older thread is indeed interesting.  Glass-as-a-substitute-for-cement in a "concrete".  Hmmmm.   Has anyone ever actually made such a material?

What about means to concentrate surface calcium sources into the 10+% range so that glass-as-we-know-it becomes feasible on Mars in those locations where SiO2 is available?  I'm looking for clear glass panels for habitats and greenhouses. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#8 2013-08-22 13:58:58

louis
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From: UK
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Re: Glass

GW Johnson wrote:

Spacenut's link to the older thread is indeed interesting.  Glass-as-a-substitute-for-cement in a "concrete".  Hmmmm.   Has anyone ever actually made such a material?

What about means to concentrate surface calcium sources into the 10+% range so that glass-as-we-know-it becomes feasible on Mars in those locations where SiO2 is available?  I'm looking for clear glass panels for habitats and greenhouses. 

GW

There was prog on Brit TV last night which showed walls made out of optical fibre and brick or similar - you could have varying levels of light coming through the wall...so it sounds possible!


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#9 2013-08-22 14:00:22

louis
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From: UK
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Re: Glass

Of course, let's not forget basalt is an easy to use and form material that should be readily available on Mars. Could be very useful for making bowls, vessels, work surface, table tops etc.


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#10 2013-08-25 21:51:07

Void
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Registered: 2011-12-29
Posts: 2,345

Re: Glass

I am interested.  Does anyone have an opinion on the dune materials of Mars?

Information I have so far originally suggested that the dunes were of Basalt, and would be chemically unstable in the presence of Oxygen and water.

However, material obtained lately suggests sand like Earth's, but finer grains.  I have also see descriptions such as glassy.

I understand that the higher latitude dunes have ices in their pore spaces, water, and perhaps CO2.

It is a bulk material, and perhaps at lower latitudes would be loose and not cemented by ices.  I suspect that not all dunes are alike chemically, but similar.

What I am after involves 3D printing of very large structures.  To visualize it simply, I would propose a cubic structure, where a printing robot melts grains of dune material on the flat surface of the top, in successive layers.  I choose this, because I hope that the machine would be able to perform it's work largely unsupervised, and would likely do so when solar power was significantly available.  It would leave "Caves" inside of the structure which would be filled with packed but not "Sintered" dune material.  Later an extraction process, likely involving humans and machines would empty these cavities.

I can think of two uses for such a structure.  Building a Martian analog of a high rise building (But with very thick walls), or a C02 condenser.

As a habitat, I think I do not have to elaborate much.  Metal airlocks would likely be fitted into well formed structure in the "Cubic Stone".  Whatever else needed.

As a condenser, I believe that the block would achieve stable temperature suitable to condense CO2 in it's interior, as a solid.  Shading would also help, but at higher latitudes would not be needed.  I also have been reading dialog here, I think that a pump raising the pressure of the Martian air mix inside would assist in the condensation process.  Of course if it would work that way, it would also yield a mix of non-condensed gasses, which may also have some value.

I do not contemplate transparent glass.

Another problem to solve is to extract the dune material, and distribute it to the top of the cubic structure, and to spread it, so that the sintering robot could do it's work.

Other shapes than a cube would be available, but I chose a cube for ease of visualization, and also because it has a flat top, allowing such a robot to have a simplified environment to work in.


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#11 2013-08-28 17:35:17

Gregori
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From: Baile Atha Cliath, Eireann
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Re: Glass

Plastic Bowls and Vessel will probably cheaper just to send with the initial colonists. They will be reusable and light

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#12 2013-08-28 17:54:01

louis
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From: UK
Registered: 2008-03-24
Posts: 3,715

Re: Glass

True, but if this is a colonisation mission as opposed to a flags and footprints mission, then the sooner we learn how to manufacture and live on Mars, the better. Also, all new products, all "firsts" on Mars, will have intrinsic value on Earth.  What Museum wouldn't be prepared to pay a lot of money for the first authenticated vase from Mars or the first item of clothing or the first art work for that matter...


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#13 2013-08-30 08:40:21

GW Johnson
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From: McGregor, Texas USA
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Re: Glass

I'm just guessing that a glass made of basaltic material will be a hard,  opaque product somewhat similar to natural volcanic glass here on Earth.  There would be a variety of uses for such a product,  ranging from tools and dishes to building material. 

There is a definite need for a transparency material.  As far as I know,  that is silica glass.  There is silica sand on Mars,  just "not everywhere" in concentrations that would be useful.  The places where it is,  should be identified.  That's where you put your transparency factory. 

Ultimately,  surface transport by truck or train will be the most practical,  but until that infrastructure exists,  you will have to fly in order to transport people and product.  The air is too thin for airplanes,  but suborbital rocket flight would work.  So,  the same landing craft that put people on Mars could be used for this,  if (and only if) they were designed from the outset to be reused with a long service life.  You just displace some propellant weight with more payload weight for suborbital flight (that is,  provided your craft was designed with the extra volume to contain the extra payload).

You will not get that kind of service out of something with a 5% structural inert weight fraction. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#14 2013-08-30 13:36:18

louis
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From: UK
Registered: 2008-03-24
Posts: 3,715

Re: Glass

GW Johnson wrote:

I'm just guessing that a glass made of basaltic material will be a hard,  opaque product somewhat similar to natural volcanic glass here on Earth.  There would be a variety of uses for such a product,  ranging from tools and dishes to building material. 

There is a definite need for a transparency material.  As far as I know,  that is silica glass.  There is silica sand on Mars,  just "not everywhere" in concentrations that would be useful.  The places where it is,  should be identified.  That's where you put your transparency factory. 

Ultimately,  surface transport by truck or train will be the most practical,  but until that infrastructure exists,  you will have to fly in order to transport people and product.  The air is too thin for airplanes,  but suborbital rocket flight would work.  So,  the same landing craft that put people on Mars could be used for this,  if (and only if) they were designed from the outset to be reused with a long service life.  You just displace some propellant weight with more payload weight for suborbital flight (that is,  provided your craft was designed with the extra volume to contain the extra payload).

You will not get that kind of service out of something with a 5% structural inert weight fraction. 

GW

Automated land trains would be the easiest approach in the first instance for moving materials (using transponder guidance systems). A light bulldozer could remove boulders and create a flat smooth path.  Robotised digging for materials should be easy where materials are at the surface.


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#15 2013-09-04 22:53:23

JoshNH4H
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From: Pullman, WA
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Re: Glass

What I would be interested in hearing would be how much silica we could expect there to be on Mars: What will the size of the deposits be?  This article suggests that you need a combination of volcanic action and water to form that kind of silica.  Wikipedia suggests that Quartz is formed in Hydrothermal veins, whose existence on Mars is presumably unknown at this time.

Having said that, I would expect that the amount of Iron needed for a Martian colony will be much larger than the amount of glass; Therefore, using the slaggy waste from which the Iron oxides have been extracted seems to me to be a perfectly good way to obtain silica.


-Josh

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#16 2013-09-06 08:17:09

GW Johnson
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From: McGregor, Texas USA
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Posts: 3,148
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Re: Glass

Hi Josh:

I would think those hematite "blueberries" would be an easy source of fairly high-grade iron ore to utilize.  Just scoop 'em up with the equivalent of a front-end loader,  and process 'em in a reducing atmosphere.  Hematite is considered a pretty desirable ore here on Earth.  Mostly iron oxide mixed with other rock minerals,  I think it is. 

Based on some of the other discussions I have seen on these threads,  mined ice could be a source of hydrogen with which to reduce the hematite.  Products could be an equivalent to pig iron,  perhaps silica from the slag (as you suggested just above),  and probably some water from the gas exhaust (on Mars,  one should not think smokestack,  should think recovery instead). 

If such a process were emplaced and operated successfully on Mars,  it could teach us here at home a great deal about how to do heavy industry far more cleanly.  There's a really nice "spin-off" for you.

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#17 2013-09-06 10:57:18

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 5,427
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Re: Glass

GW Johnson: you're right. I was a member of the Mars Homestead project, phase 1. I proposed we use those hematite concretions. They're almost pure iron oxide, in crystalline form. They are valued iron ore here on Earth because they're so pure. And the concretions at Meridiani Planum were embedded in jarosite, a very soft sedimentary rock. So the concretions could be separated by a crusher, then tumbled to knock off remaining matrix rock, then sifted to separate them. That's a very simple process, and done so often on Earth that it's well documented.

By way, Melissa Battler called them "blueberries". She was an assistant to Dr. Carol Stoker during the first days of the Opportunity mission. Melissa was a Master student at the time. She and Dr. Stoker are both members of the Mars Society. And Melissa was president of the Mars Society Canada for a while. She's now working on her Ph.D.

I also argued for the direct iron method to smelt those concretions. That starts with another crusher, this time strong enough to crush the concretions. Crush them to fines. Then use carbon monoxide and hydrogen at high temperature. This method doesn't require limestone. It also operates at a temperature not quite hot enough to melt steel, so you can use heat directly from a nuclear reactor. The method does work with pure CO, but some of the carbon dissolves into the iron. With pure CO, you get steel with so much carbon that it's brittle. You would require a Bessemer Converter to burn out excess carbon. That requires heating it to melt steel, and wasting oxygen. If you add hydrogen gas to the direct iron smelter, then it produces water instead. Or rather steam, since we're talking about +800°C to +1,050°C. Here on Earth they use as much CO as possible, because that can be made by burning coke; a lot cheaper than hydrogen. And the more hydrogen you use, the higher temperature you require. With a lot of hydrogen, you need something in the high end of the range I gave. But with a lot of hydrogen, you produce steel directly, with no need for a Bessemer Converter.

Of course you would still need to melt it to get gas bubbles out. Or could that be done by rolling hot? Don't know. Does someone here know?

But as GW Johnson pointed out, the CO2 and H2O produced by smelting would be captured and reprocessed. Converting CO2 into CO requires hydrogen, producing water: RWGS (Reverse Water Gas Shift). So this involves a lot of electrolysis.

::Edit:: Before someone challenges me on this, I should add there is a catch. The direct iron process, aka direct reduced iron process, only works with very high grade ore. It does not require any limestone, or any other flux. Ore with impurities does require flux, and requires heat to melt iron. However, hematite concretions are the highly pure ore that this process is designed for. And there are a couple smelters on Earth doing it right now. Only where they have sufficiently pure ore.

Last edited by RobertDyck (2013-09-06 15:10:26)

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#18 2013-09-08 21:05:42

JoshNH4H
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From: Pullman, WA
Registered: 2007-07-15
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Re: Glass

What I tend to wonder is if you would be able to extract the iron from high quality (but still impure) ore by simply grinding up everything and reacting it all with Hydrogen.  You could then extract the iron by centrifuge, magnet, or by the Carbonyl process (I believe that this one was suggested by Zubrin).  I don't think that there are any other metals that would be affected by this.

The SO3 in the soil would be, but logically this could be extracted by hydration or by sublimation, depending on the desired use.  Otherwise, you have Sodium, Magnesium, Aluminium, Silicon, Potassium, Calcium, and Titanium, none of which can be liberated by reaction with Hydrogen.  Any nitrates or phosphates, if present might react with the hydrogen but could be dissolved out beforehand, or low-phosphorous ore chosen.  If there are any copper or lead or noble metals contained within the "impurities" are rather valuable in their own right.


-Josh

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#19 2013-09-09 10:42:25

GW Johnson
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From: McGregor, Texas USA
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Posts: 3,148
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Re: Glass

Hi Josh:

There's iron nodules in the caliche limestone rock here on my place.  I think they're the hematite ore we have been discussing.  Not all these are round,  but all are very hard,  and fairly-easily dislodged from partly-broken limestone.  This was deposited by iron-rich water evaporating inside solution pockets in the rock. 

These iron nodules are very,  very hard,  and seemingly (to the senses) metallic in nature.  It would take some very tough,  very powerful machinery to grind them.  I'm not at all sure whether or not simple melting might in fact be the more energetically-efficient way of handling these things.  How that would impact the process you describe,  I dunno. 

I'm going to go out and try to bust or crush one.  But,  I bet I am unsuccessful with hand tools. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#20 2013-09-09 13:02:59

GW Johnson
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From: McGregor, Texas USA
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Posts: 3,148
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Re: Glass

Josh:

I went outside and found that chunk of caliche limestone with the iron nodule in it.  It’s been in the boundary of a flowerbed for a couple of decades now.  Most of the white rocks around here do not have the nodules,  but a few do.  I suspect the solution deposition happened during the ice ages,  when things were much wetter here,  than the current semi-desert climate.  With the drought the last 3 years,  the “semi” in that name looks less and less appropriate.

I busted the rock apart with a hand-held hammer and chisel.  The nodule was harder than the white caliche limestone,  but still breakable or crushable with modest hammer blows,  far easier than I expected.  This one was not round,  and actually looked like two separate deposition events within the same solution cavity.   The protruding nodule came loose from a cavity-fill layer of what looked like exactly the same iron nodule material.  Color is a very dark brown,  not red,  not black.    It was not magnetic.  I have no instruments with which to measure hardness. 

I consulted my old manufacturing processes textbook from 1969,  and found that the useful iron ores are as listed:

Ore        color    formula        iron content    where found
Hematite                  red    Fe2O3        70%        near Lake Superior   
Magnetite    black    Fe3O4        72.4%        NY, AL, Sweden
Siderite        brown    FeCO3        48.3%        NY, OH, Germany,  UK
Limonite                  brown    Fe2O3xH2O    60-65%        Eastern US,  TX,  MO,  CO,  France

The book says that hematite by far is the preferred ore.  Vast quantities of iron pyrite FeS2 are available,  but they are not used,  because of the enormous costs of getting rid of the sulfur.  Back then they roasted it,  in a separate operation (very energy intensive,  and very polluting). 

The book didn’t say,  but magnetite is magnetic,  I believe.  Not so sure about hematite,  although the deposits near Lake Superior disturb the hell out of a magnetic compass.  Been there and done that:  180-degrees out on a 10-foot baseline.  With lower iron content still,  the others ought to be non-magnetic.

Based on that table of properties from the book,  the fact that this is Texas,  and my observations made while busting-up my sample,  I’d have to venture the educated guess that my iron nodule was in fact a piece of limonite,  essentially the hydrated form of hematite,  and thus very consistent with evaporative water-based deposition in a solution pocket.  The hydration obviously reduces structural strength,  but the basic iron content is almost as worthwhile as that of hematite. 

If the so-called “blueberries” on Mars were in fact the result of water-deposited iron,  into solution pockets inside rocks long since eroded to dust,  I’d guess that either hematite or limonite might be the mineral form of the “blueberries”.  The more we think water was involved,  the more likely limonite becomes.  I kind of doubt most of the science instruments we had on these probes could really tell those minerals apart,  anyway.  The iron contents are just too similar. 

No more than it took to bust the nodule that came from my garden rock,  I have to revise my original opinion,  and agree with you,  that crushing-to-powder is quite feasible,  and with machines not so very large and powerful,  after all. 

So your reduction process looks very,  very feasible to me.  (No more than I know,  of course.)

To this old engineer,  it sure would be fun to establish the first steel mill on Mars!

GW

ps - I can't get the table to space right.  It looks perfect in edit mode.  Sorry about that.

Last edited by GW Johnson (2013-09-09 13:04:52)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#21 2013-09-10 13:05:26

JoshNH4H
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From: Pullman, WA
Registered: 2007-07-15
Posts: 2,327
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Re: Glass

Unfortunately we don't have support for LaTeX on the forums, and they automatically eliminate spaces.  Using periods in series is my method of choice, although hyphens, underscores, etc. (especially in combination with the underline tags) work well.

Another technology to keep our eyes on is Iron electrolysis.  They're working on it now.  Link here.  That anode is just stainless steel, by the sound of it.  The procedure wouldn't make much sense on Earth-- Electricity is more costly than coal, and probably less efficient too-- but on Mars it makes scads of sense, if you have the pure ore.  Why electrolyze Hydrogen to burn with Iron Oxide, when you can just save the step and electrolyze the iron straight?

An alternative to doing the smelting with impurities present would be separation by density after crushing.  Iron oxides should be some of the densest in the soil, so it'll be pretty easy to skim off the top layers until the Iron oxides are pure.  I don't know which procedure is best, but it's definitely something to play with.


-Josh

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#22 2013-09-12 08:42:51

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,148
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Re: Glass

I like the electrolysis idea for Mars.  The combustion-based traditional methods are an artifact of our oxygen-bearing atmosphere.  Things are vastly different without that environment. 

Dunno if you can simply separate minerals by crushing,  they may still bind together until your particle size is of molecular dimensions.  That's impractically fine.  Even colloidal sizes are very expensive to do,  and that does not undo chemical binding. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#23 2013-09-12 11:03:45

Decimator
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Registered: 2011-11-20
Posts: 39

Re: Glass

You can use code tags like so:

Ore		color	formula		iron content	where found
Hematite	red	Fe2O3		70%		near Lake Superior	
Magnetite	black	Fe3O4		72.4%		NY, AL, Sweden
Siderite	brown	FeCO3		48.3%		NY, OH, Germany,  UK
Limonite	brown	Fe2O3xH2O	60-65%		Eastern US,  TX,  MO,  CO,  France

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#24 2013-09-12 11:06:01

Terraformer
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From: Lancashire
Registered: 2007-08-27
Posts: 2,823
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Re: Glass

Decimator wrote:

You can use code tags like so:

[code/]
Ore        color    formula        iron content    where found
Hematite    red    Fe2O3        70%        near Lake Superior   
Magnetite    black    Fe3O4        72.4%        NY, AL, Sweden
Siderite    brown    FeCO3        48.3%        NY, OH, Germany,  UK
Limonite    brown    Fe2O3xH2O    60-65%        Eastern US,  TX,  MO,  CO,  France
[/code/]

...though obviously with the / after code removed.


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#25 2013-09-13 10:13:07

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,148
Website

Re: Glass

No idea what a code tag is.  I'll try the periods.

Thanx,

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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