[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re:

As a geologist, I can verify that the description of
the black and red varieties of lava rock formation are
correct.  There is a slight difference in the valence
of the iron in the two and that is about the only
difference.  Almost all of the iron in the red variety
is iron hydroxide Fe(OH)3 (the mineral hematite) while
the iron in the black lava rock is Fe3O4 (the mineral
Magnetite).  Therefore the red variety is more
oxidized than the black variety, and that is about the
only difference.
--- "Stoecker,Michael,FRANKLIN PARK,NC&C"
<michael.stoecker at us_nestle.com> wrote:
> I know no body asked, but...
> I found this site about lava rock: 
> http://www.sfmining.com/lava_rock.htm
> I noticed that the black type weighed 200 lbs./ton
> more than the red.  A
> quick call to them, and I found out that the black
> is less porous than the
> red and hence more dense and thus weighs more per
> ton.  The person I spoke
> with felt that there was no real chemical
> composition difference between
> them.  He did say they were mined 300 miles apart.
> Another site I found suggested that the color
> variance was due to the
> oxidizing effect of the environment at the moment
> the magma comes out of the
> volcano.
> BTW, "lava rock" actually refers to two similar
> things, but very different
> for our purposes.  One is magma that flows out of
> the volcano  and stays on
> the ground [very dense, few pores] and the other
> refers to magma that is
> blasted into the air and undergoes a very rapid
> expansion and cooling
> falling down on top of itself in piles around the
> volcano.  It is these
> piles that are mined to get the porous lava rock in
> which we are interested.
> mike stoecker
> 
> 
> 
> 
> 
> ---------------
> See http://www.aka.org/AKA/subkillietalk.html to
unsubscribe


=====
Allen H. Johnson
132 Whispering Oaks Dr.
West Chester, Pa.  19382

__________________________________________________
Do You Yahoo!?
Get email at your own domain with Yahoo! Mail. 
http://personal.mail.yahoo.com/?.refer=text
---------------
See http://www.aka.org/AKA/subkillietalk.html to unsubscribe
References: