which element to mine for on Mars

So, there is a Mars colony, 30,000 people across several habitats (Geodesic domes). It's about 2070.

Air, water, food, and power are not problems, but resupply from Earth isn't going to happen, they are stuck with what they have, forever.

As a sub-plot item, two secondary characters are arguing about what to go for. They don't have the resources to do both, and the one they choose could be critical. I haven't yet decided whether it's "Thank god we went for X" or if it's "Oh crap, wish we'd gone for Y" not sure it matters.

I sort have an idea for 2 opposing choices.

1. They can build a "railway" to a local Iron ore deposit, and mine Iron, which is a useful structural material. It's cheap and easy to produce and they get immediate short term benefits - they can build more living space, they can expand their little rail-network beween some of the more isolated domes, Steel is a useful materian and they can build magnets and motors out of it. Good stuff.

2. They go over land to get Aluminium. A better structural material in the long term, but not so useful immediatly. The kicker for me, is that they will get some Gallium from mining Aluminium, which they are short of, they only have about 18 months supply, and it's very important to their technology.

So Aluminium is the more difficult choice, but they have to get it at some point, Iron is quick and easy with immediate payback, but maybe they could just ignore it?

Do you have any other ideas for competing materials they could go for, that would be critical to a high tech colony on Mars for it's long term viability? Any thoughts on why you might go for one instead of the other, or should they be going for something else instead?

Any thoughts appreciated.

If air, water, and food are not critical, the next thing any long-term-survival plan needs is what IS critical. If your Techno Whizzjig needs gallium, and they only have an 18 month supply of gallium, and don't necessarily need iron ore, then the only logical conclusion is that they'll go for gallium-bearing aluminum deposits. Additional structural materials mean less than nothing if you're going to run out of Techno Whizzjig Fuel by getting it.

I am also doing a story on Mars, but they have same situations. The things on Mars is what they have and Earth is not a great source of retrieving resources.

I had made up a microbrial organism that was a necessity. They are used for the algae to grow and maintain oxygen, albeit, still not enough for 100% breathable atmosphere as they also need some sort of large scare geothermal stimulation IE a nuclear bomb or an asteroid.

but that is what they are mining for top priority is a microbial organism they need.

Helium-3 or Tritium may be abundant resources for energy.

Rare earth minerals is an option if you interpolate that earth has expended theirs.

To bad there isn't a place they can mine that has a Iron Aluminum mix or alloy.

Maybe something that is added to the metal of the domes to provide shielding from radiation that reaches the ground and which breaks down over time. With the Martian atmosphere being so thin as it probably is I could see the need for something to shield against solar radiation and things like cosmic rays which normally are protected against by a thicker atmosphere. Something made of a mixture of materials. A composite or alloy of some sort that covers the surface of the domes. They have the means to make the material and the raw ingredients are there for the taking but they find that the supply in their area isn't as large as they had first thought and have to go further afield to find more. Otherwise people are going to start getting sick from radiation sickness.

Don't forget the human element. Think of the story like a body. Iron or aluminum is like the skeleton. The human tensions are the flesh that is attached to the skeleton. The metal dispute gives you structure, but it probably should be about more than just the metal. I suppose some factions support iron and some aluminum, but why do they support one against the other? Do they have the interests of the colony at heart, or are they guided by their own interests? Who wins and who loses if you choose one metal instead of the other? Many things in life are decided not because of rationality, but because of the power of the factions.

I think the gallium issue forces the choice in favor of aluminum, and thus takes away the dilemma. If you must have gallium, and you get the gallium from mining aluminum, then you must mine aluminum. Making gallium mining a separate issue keeps this dilemma alive.

frame it something like Original Dome is old and falling apart and needs the structural iron, and if anything goes wrong before iron supply, people will have to abandon site and move into other domes overcrowding them till iron is extracted.

Or we go for X which will put off the extraction of iron, but when we have it, it will mean the extraction of iron will happen more quickly and efficiently. we dont have to worry about something happening. Original Dome will be fine until we get our efficiency up and if not, we double up for a while.

sorry for being absent from the thread - lost internet!

I see the point about the Gallium being a no-brainer, if they need Gallium as a critical element, it's difficult to argue for anything less critical.

So maybe I need to add a sweatner to the Iron - a good location for building, or something. I like the analogy to the frame of the building and the social elements.

The colony is run by a semi-democratic council, and they want to do the best for the colony, however they have to balance social issues - living space and entertainment products - against technology issues - more of the critical element (in this case gallium). The council decides on the social side - keep the people happy, which isn't an evil or bad goal, just shortsighted. The technical guys knows it's shortsighted, and can see more clearly the problems down the road if they don't obtain a new source of gallium.

The two characters involved are friends/ish but one is very technical "we need gallium, without it our technology goes away" and the other one is "our comittee agreed we need to mine Iron to expand, they don't see the technlogy issues as being so critical, we have spare parts, we have time, what's the biggie?"

I like the idea of selecting somethist technology, maybe they need a mineral for a vitamin they are low on, then the choice is between technology for long term survival, or god short term health.

I'll think on it some more.

I don't want it to be a big thing, after all most of the action is associated with an assault on the orbital space station around earth that is trying to dictate to the rest of the solar system.

I also need to consider what the long term consequences are, I see this ultimatly as a victory for the techincal guy "I went round your backs to get the Gallium, and it's a good job I did, or we'd all be dead." type of thing.

There is also the question of why air, water, food and power aren't in short supply to consider. I mean Mars isn't the most hospitable environment (though more so than other planets in the solar system save earth itself) so why aren't they in short supply but things like gallium and iron are? In the past when someone set up an outpost somewhere it was by a river or along a trade route of some sort. That's how villages which later grew into towns and cities got started. London for example was a Roman fort and Oxford was originally a spot on a river where cattle could be gotten across from one bank to the other (where Oxen could ford the river). So your colony has to have had reasons for building their domes where they did and not some other spot on Mars. Maybe someone forced the issue for political or financial gain (it happens) and the issue of supplies of the sort of things needed was swept under the carpet. Or maybe some of the things that are said to be in good supply really aren't and the heads of the colony are trying to keep it under wraps while sending out parties to get what is needed under the guise of going for something else. If the iron is in the form of iron oxide for example which can be processed to remove the oxygen for air and their supply is in need of stockpiling and so industries that need it (such as some welding jobs and fuel for space craft) are at a minimum or something that could raise tension.

Actually, the main thing keeping Earth relatively radio-active-ion free is the magnetic field. Which Mars does not have. So, Iron super magnets to help shield the domes?

Energy is never free, nor limitless. There are always cost. Where does their power come from?

If one has a limitless source of power, then why is there no traffic between the home world and the colony? A limitless source of power makes travel cheap! A limitless source of power makes for cheap food and air, there becomes no reason to limit the population. That means there would be plenty of bodies to work multiple sites, in my opinion. Then there are out lying sites, people who should naturally have different ideas, beliefs. If there is a need to build a rail system to reach another location, it can't be close, again with limitless power there is no reason they couldn't get bodies from other locations. With limitless power it would change the things we value, the things that matter to us.

Say one group wants to mine, and another wants to put on plays, make people feel.

Mars, the red planet. Red because of all the iron oxide! How believable is it, that your group would really pick a spot far from iron? Iron oxide that could be refined to give not only iron, but oxygen as well? How do they scrub the carbon dioxide from their air? I'm sorry but to me it is the little things, that make a story flow, or hang it up. Perhaps you are a really skilled writer and can make us believe anything... Then again perhaps if you were that skilled you would not be here asking for help? Part of it in crafting a world has got to be about how believable it is, or isn't. How based in science it is or it isn't. This is Science Fiction, right? Not fantasy were the reader knows going in that it doesn't have to make sense. Do you really want to create a world with limitless power, and high technology, where people are engaged in risky back breaking work to mine, iron? The first things we have placed on Mars, are robots. With limitless power, would one really risk their body going after something as cheap and common as iron? We've got drones today, we've got robots that function at interplanetary distances ~ why wouldn't one send robots to gather up the rust on Mars surface?

Just my two cents...

What if water and air are a finite resource, but they were ok because there was a good recylcing plant that is now breaking down? Then the argument can be between those who want to rebuild the (complex) recylcing plant with Unobtanium, versus those who want to mine for water and oxygen-bearing rocks to start the terraforming they have been putting off up till now due to the difficulty involved. It would, of course, simply be symptomatic of those who want to keep the good old days going versus those who believe that the good old days are gone forever and will never return.