Making rocks is not a very complex process- it happens all the time at volcanoes all over the world. In fact, molten rock isn't all that hot compared to the melting point of many modern materials. Iron, in fact, melts at a higher temperature than cool lava. I propose heating rock until it melts in a "good" blast furnace (admittedly by good in this case I probably mean one of those crazy solar things or maybe even a small reactor) and pouring it into a mold. The result is a cast stone that can be used for building. Stone has a lot of advantages for energy efficent and aesthetics, but it's hard to get these days and harder to work. This allows scrap stone to be processed into shapes that are easy to use.
-- Madcat, Apr 29 2007

Artificial stone and method for making http://patft.uspto....73484&RS=PN/4173484
[ldischler, Apr 29 2007]

This reminds me of a much less plausible idea I had in school. I wanted to melt wood by heating it in an argon filled kiln. My idea sucked but yours should work.
-- stilgar, Apr 29 2007


Iron and steel are cast in sand molds. What are you going to use for molds here?
-- Galbinus_Caeli, Apr 29 2007


Damn. Ian beat me to it.
-- hidden truths, Apr 29 2007


A bun, but only if you set up production near Kilauea or any other active volcano and use *real* magma. [+]
-- nuclear hobo, Apr 29 2007


and would the work on the very first stone to emerge from the forge be given over to he who is without sin?
-- xenzag, Apr 29 2007


Psst, [xenzag], [it] already did that gag.
-- coprocephalous, Apr 29 2007


I was going to post this as a new idea, but perhaps it would fit better here.

During the process of producing metal, rock is already heated up until at least some of it melts.
I saw a program on TV last night where the process for disposing of Nickel slag was to load it into large retorts then pour it down a slope. To prevent it building up, it's then scraped up with powerful bulldozers. These need constant servicing because of the hardness of the material.

After googling, I believe that a fraction of this is ground up for use in sand-blasting, and the remainder goes to landfill.

Therefore nickel slag would be an ideal thing to trial rock-casting with. It's already molten, and is largely a waste-product. The only disadvantage may be that it's probably in a fairly remote area, but the freight transport links are likely to be good.

I think that a sacrificial mould could be formed of densely packed sand. The rock might melt and absorb some of the surface sand, but I would expect this to be fairly predictable.

Possibly the slag from producing other metals would be available on a large scale as well.

...

Apparently 'without' used to mean outside - as in the hymn "There is a green hill far away without a city wall". So just rename a town nearby 'Sin' and you're good to go.
-- Loris, Aug 21 2009


//it's hard to get these days//

Really? Most of the earth's crust is stone.
-- ldischler, Aug 21 2009



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