Hey Jim,

Gold, huh? Break of a quarter sized piece and send it to me. I don't return samples though because of the million I receive every day ;-)

Kidding aside, I guess there are nifty formulas floating around that make assumptions on the matrix composition and that you've long since figured out that your rock doesn't fi the composition assumptions. If you have to know and that is more important than the whole specimen as a collectible or memento, ah the meteorite conflict rears its ugly head - I have to cut it to know what it is...

My thought would be make a nice slice right down the middle to make two matching halves you can polish for aesthetics. Look at it for what that tells you as to the gold aggregation in it. Maybe save the cutting dust to check for gold content of thar. Then, check the density of each half to see if they agree. If they don't that will be a clue that something's up with the rock. Or you could just keep it as is to enjoy and imagine it as you wish! Anyway good luck ;-0 -doug


-----Original Message-----
From: Jim Wooddell <nf11...@npgcable.com>
To: meteorite-list <meteorite-list@meteoritecentral.com>
Sent: Sat, Apr 14, 2012 11:28 am
Subject: Re: [meteorite-list] OT: For the Geologists and Math Wizards!


Hi Doug and all!

Thanks for the answers.

My thought was, prior to posting the questions here, that you could not have
a calculation that would result in a density less than the less dense
material, if the formula was correct where you have known densities of two
specific minerals.
To add to that here, with melting or morphing or whatever, I contend you could not have a calculation that would result in a lower density than any of the known densities of any known minerals or mixtures there of. However,
if there are unknowns, then I do see where is it very possible where it
would totally hose the results.
I stated that in another forum and then thought about it for a while and thought, "Oh Shxx, I had better ask people way more knowledgeable than I".
I put the OT in the subject line cause it may or may not relate to
meteorites....I just knew some great minds are on this list.
Specifically, I have a 65g rock with a lot of gold in it. While trying to determine the percentage of gold in it, this particular rock is breaking all the rules of engagement...to the point I am about ready to take a hammer to it and simply do it the old fashion way with mercury....except I don't have
any mercury!  That would be the part that is totally off topic for this
list...except I found the gold when meteorite hunting! Using some of these wiz bang gold formulas (found on gold forums) I am coming up with negative numbers and one with minus 130% gold! I do not know how on earth I could be off by that amount using any of the areas known minerals or combinations of. Driving me nuts! It is such an awesome specimen, I hate to take a hammer to
it...but two days of number crunching and testing is not "panning" out.

Jim



----- Original Message -----
From: "MexicoDoug" <mexicod...@aim.com>
To: <c...@alumni.caltech.edu>; <meteorite-list@meteoritecentral.com>
Sent: Saturday, April 14, 2012 7:42 AM
Subject: Re: [meteorite-list] OT: For the Geologists and Math Wizards!


Jim,

In a practical sense, this is quite possible since there are more
possibilities, where your question could be taken as too ambiguous.
Specifics - what are you really after? I'm thinking if this relates
to
meteorites you might have some concretions in mind as well, or
perhaps
melting and there are rarely "just" two minerals present in nature.
When
I mixed the concrete to fill the hole in the driveway, the hydration
(a
chemical modification) causes a structural change as well which
contributes to a volume change, and it was certainly more slurry than
the
sum of the cement and sand, to adjust for the water. Some hydrations
are
reversible and others aren't. In nature for the organized mind,
things
usually go to hell in a handbasket since it is usually an open,
complex
system where everything and then some goes.

If you like math, some engineers probably are very concerned about
shrinkage or expansion of concretions for the times we drive over
bridges,
etc:

maybe this gives further insight, I googled blindly:

http://www.byg.dtu.dk/upload/institutter/byg/nyheder/trb-06-1571-as%20submitted%20final.pdf

If two minerals are melted together, it is quite possible they will
form a
new crystal or amorphous structure, perhaps not even a clear chemical
modification, but rather just reordering on a molecular scale that
don't
result in voids, but do result in a new density without adding gases,
etc.
I guess it might be a new mineral, but I'm not sure I know the
precise
definition of a rock or mineral so I'd think of it this way.

Kindest wishes
Doug


-----Original Message-----
From: Chris Peterson <c...@alumni.caltech.edu>
To: meteorite-list <meteorite-list@meteoritecentral.com>
Sent: Sat, Apr 14, 2012 2:08 am
Subject: Re: [meteorite-list] OT: For the Geologists and Math Wizards!


If the two combine as some sort of conglomerate (like a breccia), and
the combination doesn't result in voids, then the bulk density can't
be
lower than the density of the lowest density material. But if the two
combine chemically, resulting in an alloy or in the formation of
different minerals, certainly the bulk density could be lower than
either of the constituents (because you could have an increase in
volume).

Chris

*******************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

On 4/13/2012 9:04 PM, Jim Wooddell wrote:
Hi all!

I have a question that relates to meteorites...sort of.


If I have two minerals that are combined that have two different
densities, could the bulk density ever be lower the density of the
mineral with the lowest density?

Examples (to make it easy) Mineral 1 = 3g/cc Mineral 2 = 15g/cc

IOWs could I ever have a density lower than 3g/cc???

If yes, can I please see the math?

Thanks

Jim

______________________________________________

Visit the Archives at
http://www.meteoritecentral.com/mailing-list-archives.html
Meteorite-list mailing list
Meteorite-list@meteoritecentral.com
http://six.pairlist.net/mailman/listinfo/meteorite-list

 ______________________________________________

Visit the Archives at
http://www.meteoritecentral.com/mailing-list-archives.html
Meteorite-list mailing list
Meteorite-list@meteoritecentral.com
http://six.pairlist.net/mailman/listinfo/meteorite-list

______________________________________________

Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html
Meteorite-list mailing list
Meteorite-list@meteoritecentral.com
http://six.pairlist.net/mailman/listinfo/meteorite-list

______________________________________________

Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html
Meteorite-list mailing list
Meteorite-list@meteoritecentral.com
http://six.pairlist.net/mailman/listinfo/meteorite-list

Reply via email to