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> Almost certainly not considering how vanishingly rare ice asteroids are to date

Not almost certainly anything. The asteroid belt is a plentiful source of water and will be for long after we've colonized other planets, given the volume present. See the self-regulating snow line - http://www.galleries.com/rocks/asteroids.htm

> Not that water could repay the cost of getting at it anyhow.

I'm not sure if that's trolling. Water can be made unusable, has been, and continues to be. Potable water is literally priceless. The primary cost in obtaining resources from stellar bodies is in fighting gravity wells. Asteroids are convenient in that they minimize this cost.

Did you look it up? It is apparently the chemical formula for a mineral called... wait for it... cummingtonite.

dual purpose, can be also used as flame shield...

"One form of cummingtonite (a variety called "amosite") is asbestos-form and can be used as asbestos. Asbestos has many industrial uses despite some health risks and is made from different minerals, all with a fibrous habit. Serpentine and tremolite asbestos are considered the better varieties due to their greater flexibility and tensile strength, but cummingtonite asbestos has its uses and is being mined for this reason in South Africa."

http://www.galleries.com/minerals/silicate/cummingt/cummingt.htm

http://www.mindat.org/min-1170.html

http://webmineral.com/data/Cummingtonite.shtml

Someone's going to be (Mg,Fe)7Si8O22(OH)2

All time best geek sig!

That's funny. My computer is made from sand.

That's funny, sand is the remains of eroded/weathered rock. Also, most of the Earth's mantle and crust are made up of silicate rocks (wiki). My sand is made of up of local random silicate minerals, maybe some feldspar, quartz, biotite and muscovite (my sand is weathered/eroded granite).

The silicates are the largest, the most interesting and the most complicated class of minerals by far. Approximately 30% of all minerals are silicates and some geologists estimate that 90% of the Earth's crust is made up of silicates. With oxygen and silicon the two most abundant elements in the earth's crust silicates abundance is no real surprise.

Ref

Scientific Symbol: ASS.

AsS is taken: it is the symbol for realgar.

Yeah, but they're shiny.

Yeah, but they're shiny.

nay, sir. It isn't as deadly as it is beautiful:

http://www.galleries.com/minerals/sulfides/realgar/realgar.htm

Here's the abstract of the original paper. I can't give a link because it requires a subscription to Science, but I think this is enough.

Detection of Methane in the Atmosphere of Mars
Vittorio Formisano,Sushil Atreya, Thérèse Encrenaz, Science, Vol 306, Issue 5702, 1758-1761, 3 December 2004

We report a detection of methane in the martian atmosphere by the Planetary Fourier Spectrometer onboard the Mars Express spacecraft. The global average methane mixing ratio is found to be 10 ± 5 parts per billion by volume (ppbv). However, the mixing ratio varies between 0 and 30 ppbv over the planet. The source of methane could be either biogenic or nonbiogenic,including past or present subsurface microorganisms, hydrothermal activity, or cometary impacts.

Later in the article, they expand on what they mean by "hydrothermal activity."

On the other hand, methane could have been formed by magmatic processes or stored in methane hydrates for later release to the atmosphere. Terrestrial volcanoes are not a big source of methane, and large-scale volcanism has not taken place on Mars for over 100 million years. However, small-scale outgassing of methane cannot be ruled out. A potentially larger source of methane than volcanism may come from the alteration of basalt at a temperature <150C, a process that also results in the wet-phase conversion of original CO2 into CH4 in a subpermafrost aquifer. In their chemical equilibrium computer model, Wallendahl et al. calculate that as much as 0.2 bar, ~1015 tons, of CH4 could have been produced if the only source of C in this region was the CO2 initially present in the crustal pores. Methane could have been sequestered in stable methane hydrate and gradually risen to the planet's surface. The rate of release to the atmosphere is unknown, but if one assumes that leaking has been taking place at a uniform rate over time, it would amount to ~200,000 tons year-1, which is much greater than the 100 tons or so per year needed to maintain a steady-state mixing ratio of 10 ppbv of CH4 on Mars today. Even if methane from the hydrate is being released at a rate that is a factor of 1000 slower, it would still be sufficient to account for the observations. Finally, recent laboratory experiments confirm abiogenic generation of methane in mineral-catalyzed hydrothermal reactions of CO2 and H2O at 390C and 400 bars, conditions that are likely to be encountered in subpermafrost aquifers or deep under the polar ice on Mars. Moreover, the catalyst used in the experiment--Fe-Cr oxide--is also believed to be present in the martian rocks.

Note that Olivine is Magnesium Iron Silicate (http://mineral.galleries.com/minerals/silicate/ol ivine/olivine.htm), so that's not the same as the Fe-Cr considered here, but it's not all that far a stretch either.

--Greg

Graphite and Diamonds are different polymorphs of Carbon. They have different structures and different properties.
See this site for more detals.

How about using it as a tip for drilling? If so, you'd need to work out how much pressure it could sustain, as well as its hardness factor (on the Mohs Hardness Scale). If it would have explosive tendencies at high pressure, I suggest it not be used to drill for oil. However, it could replace natural diamond to drill for metals, provided it is "harder" than them. If it should explode while drilling for metals, this could be rather useful...

You mean like 11? As you said, the Mohs scale assigns ordinal values to make relative comparisons, not absolute ones. For a scale which makes absolute comparisons between the standard minerals see this website.

I think the abstract said "at least comparable to cubic diamond".

That would change Mohs hardness scale if it were harder.

Hardness is traditionally measured using the Mohs Hardness Scale

"Oh God, I'm Cumming!"

Yeah, sure, I'm cummingtonite!

((Mg, Fe)7Si8O22(OH)2 , Magnesium Iron Silicate Hydroxide)

The NASA scientist held up a sample of Jarosite. For the curious, here's a definition. Note -- the page referenced has several very cool links for more information.

THE MINERAL JAROSITE
Chemistry: KFe3(SO4)2(OH)6, Potassium Iron Sulfate Hydroxide.
Class: Sulfates
Group: Alunite
Uses: Only as mineral specimens.
Specimens
Jarosite is not a common mineral. It is closely related to the mineral natrojarosite. Jarosite is isostructural with natrojarosite which means that they have the same crystal structure but different chemistries. In this case, jarosite contains potassium instead of natrojarosite's sodium (natro is derived from the Latin for sodium, natrium, from where sodium gets its symbol, Na). The two minerals are difficult to distinguish without a chemical test.

Both minerals are isostructural with alunite with a formula of KAl3(SO4)2(OH)6, who lends its name to the Alunite Group of which all three minerals belong.

The symmetry of jarosite is the same as the members of the Tourmaline Group. Crystals of jarosite however do not form prismatic crystals like those of the typical tourmaline mineral. Jarosite's crystals are more flattened and resemble nearly cubic rhombohedrons. The "rhombohedrons" are actually a combination of two trigonal pyramids.

PHYSICAL CHARACTERISTICS:
Color is an amber yellow or brown.
Luster is vitreous to resinous.
Transparency: Crystals are transparent to translucent.
Crystal System is trigonal; 3 m
Crystal Habits include tabular to flattened rhombohedral looking crystals. The "rhombohedrons" are actually a combination of two trigonal pyramids. Crystals are somewhat scarce and small, more commonly as earthy masses, films or crusts, botryoidal and granular.
Cleavage is good in one direction but only seen in the larger crystals.
Fracture is uneven.
Hardness is 2.5 - 3.5.
Specific Gravity is approximately 2.9 - 3.3 (average to slightly heavy for translucent minerals, but hard to obtain from crusts)
Streak is a pale yellow.
Associated Minerals are barite, turquoise, galena, goethite, limonite, hematite and other iron minerals.
Notable Occurrences include Jaroso ravine, Sierra Almagrera, Spain and Iron Arrow Mine, Colorado; Maricopa Co., Arizona; Idaho and California, USA.
Best Field Indicators are crystal habit, associations, color and hardness.

Olivine forms volcanically, and will alter quickly (on a geological scale) into another mineral called Serpentine, which is why finding it here is very suggestive that both during its formation and subsequence existance on Mars, the rock has remained dry. It's not such a surprise that olivine has been found, is it?

For the sort of money they're talking, you could build a lot of renewable generation, and it'd be working now, not in 2010.

Check it out.

According to Mining bacteria's appetite for toxic waste

A complex community of microorganisms thrives by "breathing" oxides of sulfur, iron, aluminum and even more hazardous compounds like the uranium and other radioactive elements. As the microbes obtain their oxygen from soluble uranium oxide, for example, they transform it into a highly insoluble form called uraninite.

The article does not say what is uraninite. Uraninite is the primary ore of uranium. Uraninite is a reduced form of uranium which appears in places where there is few oxygen. So what the bacteria do, is consuming the oxygen and altering the environment of uranium so it changes the environment so uranium alters into uraninite faster which is only stable when uranium cannot associate itself with oxygen.

Ok now, according to The Mineral URANINITE:

Uraninite is a highly radioactive and interesting mineral. It is the chief ore of uranium and radium, which is found in trace amounts. Helium was first discovered on the earth in samples of uraninite.

So we have changed a radioactive material into a highly radioactive and interesting mineral ? Wow that's a deal =), now it is not only radioactive but interesting also.

I think Windows is going towards another element: Palladium

Or perhaps Pyrite.

(though I know that's not an element)

A couple of trivialities:

I learned about "paddy wagon" in Chicago, which is well-known for St. Patrick's Day drunkenness. With that and spades, I figure if I'm going to insult someone, I want to do it intentionally.

On gems -- the aluminum oxide base is called corundum and can be either ruby or sapphire. The tidbit I know about domestic corundum is that it was used to make the finishing touch on the National Monument, a cap made of aluminum, at the time the hot new metal and expensive as heck.

On Al and corrosion. (I'll read most anything.)

Locking it up in the glass of a CRT is a pretty damned good way to keep discarded lead out of the water table. In fact, I can't think of a better one. Can you?

Yes.

My argument is that 99.9% of environmental scientists are neither chemical nor physical engineers.

Unfortunately, the reverse is true. 99.9% of chemical and physical engineers are not environmental scientists.

Environmental science is hardcore - it requires chemistry, biology, earth science AND a specialised series of courses. I picked the university of sydney at random (high google page rank,) but the requirements are similar here at Columbia.

The environmental scientists know their chemistry - the chemical engineers don't know their biology, meteorology or geology, which is where the problem lies (I don't want to badmouth everyone in that discipline; I'm a molecular biologist but I make an effort to keep abreast of the broader context of my work. I know some chemical engineers who are quite savvy on what happens outside of a synthesis facility.)

Actually, my partner Vikki was not at all interested in a diamond. She doesn't find them attractive. What she wanted was a top-grade emerald, which is more beautiful in her eyes. The deep rich green-with-just-a-hint-of-blue is her color :)

But if you're looking for a rare stone that's also pretty, and will certainly hold its value, try taaffeite Several of these gems have been found, as has a location for low-grade, not gem grade, material, but to date the source of gem-grade taaffeite remains undiscovered. It's far too rare to be used as a major source of terrorism funding :)

There has always been transparent aluminum.