The use of the words chert vs flint in the States to describe
cryptocrystalline quartz is based on regional speech variation and state
of manufacture, not color, luster, or any objective standards.
Archeologists and those referring to human worked rock generally use
flint or flints.

Therefore, chert nodules can be worked into flint arrowheads.
Nobody said it had to make sense.
Jo

hanson wrote:

"Jo Schaper" wrote in
message ...

hanson wrote:

element or compound in tree bark that it burns with too much ash
"Bob" wrote in message
...


"Farooq W"
| More surprising the uptake of heavy metals especially
| Th and U by the plants...Barium is abnormally high or the
| soil on which that tree grew was rich in barium ores!


On Sat, 11 Mar 2006 02:27:31 GMT, "donald haarmann"
wrote:

The up take of uranium by plants is well know. See for example :-
Botanical Prospecting for Uranium on La Ventana Mesa, Sandoval
County New Mexico. US Geological Survey Bulletin 1009-M. 1956.
Some plants uptake serious amounts of selenium.

[Bob]

A Berkeley group is developing the use of a plant for Se
decontamination of soil. It is in field testing. (I could probably
find a ref if someone wants it.)
Then there are the Ni accumulators, which have several percent Ni in
their sap, nicely chelated (citrate, I think).
bob


[hanson]
=1= I posted this into sci.geo.geology in hope to get some views
from the geos' camp about the popularity & effectiveness of BP.
=2= As what/which compound does Si get into solution from the
calcogen silicates, considering that SiO4-- is stable only at
pH 11 in aq?
=3= in what soluble or sol-gel form is Silicon taken up
and transported in/to the plant (at a pH range ~ 7)
=4= As what/which compound is Si stored in the plant?
=5= and what function does the Si have in the plants?

[Jo]

I don't know the answer to your question, but I would look at
Equisetum -- aka scouring rushes. They have extremely high
Si uptake. [1] As a primitive plant whose chlorosphyll is incorp'd
in the stems, the Si, is used as a supporting structure. [2]
Also, the Na, K, Ca group are also metals utilized by plants. [3]


[hanson]
Thanks Jo. AFAYK, is [1], such a high Si uptake, common to
all such primitive plants (Fern, Lichen etc)? If yes, then there's
here an interesting link to the origin of multi-cellular plant life.
In marine plankton, the radiolarians, all do have skeletons made
of beautiful microscopic SiO2 structures.
What Si chemistry and physics is involved in their existence &
growth? -- How & in what form do they extract Si from sea water?
What chemical Si-reactions are involved in this transport?
What soluble silicates are there in ocean water?

I have no problems with [3] presence at all, not even with [2]
using the rigid SiO2 networks as a the basic inorganic frame
around which the "living" CHNO networks grow and harden
(a bit like in a fiber-glass analogy)... But what I have not seen
a good/elegnat explanation yet for in what form this Si4+ or
H4SiO4 is transported into and through the plant.
hanson

hanson,
I am not a botanist, nor a botanic chemist. I would suggest you go to
a local botanical garden, or the botany section of a college library and
look up such things as 'natural terrestrial communities' 'acidic soil
ecosystems''alkaline soil ecosystem'(to see how the other half lives)
'sandstone glade' 'chert glade' 'igneous glade' and any other
combination of silic rock name plus landform (prairie, forest, savanna,
fen, bog, etc.)

As a generalization, more primitive plants do tend to populate more
silic environments, (pines on sandstone, deciduous trees on limestone)
but these are generalizations, with many exceptions as some trees and
plants (blackjack oak, post oak) do adapt to silic environments.

A good naturalist can walk through an area and accurately predict either
the rock or the plants if they know the other, plus the amount of
retained moisture and sun which an area gets.

I had to look up all this stuff when I did my thesis--in order to relate
water chemistry to some of the plants, and their possible interaction
with travertine deposition (i.e., was the water, the slope or the plants
controlling deposition) and I found more info than I could absorb or use
by just browsing in ecology,agronomy and silviculture texts.

"Michael Hearne" wrote in message
ink.net...
hanson wrote:
"Edward Hennessey" wrote in message
ink.net...

"Jo Schaper" wrote in
message ...

hanson wrote:

element or compound in tree bark that it burns with too
much ash

"Bob" wrote in message
m...


"Farooq W"
| More surprising the uptake of heavy metals especially
| Th and U by the plants...Barium is abnormally high or
the
| soil on which that tree grew was rich in barium ores!


On Sat, 11 Mar 2006 02:27:31 GMT, "donald haarmann"
wrote:

The up take of uranium by plants is well know. See for
example :-
Botanical Prospecting for Uranium on La Ventana Mesa,
Sandoval
County New Mexico. US Geological Survey Bulletin 1009-M.
956. Some plants uptake serious amounts of selenium.

[Bob]

A Berkeley group is developing the use of a plant for Se
decontamination of soil. It is in field testing. (I could
probably find a ref if someone wants it.)
Then there are the Ni accumulators, which have several
percent Ni in their sap, nicely chelated (citrate, I
think).
bob


[hanson]
=1= I posted this into sci.geo.geology in hope to get some
views from the geos' camp about the popularity and
effectiveness of BP.
=2= As what/which compound does Si get into solution
from the calcogen silicates, considering that SiO4--
is stable only at pH 11 in aq?
=3= in what soluble or sol-gel form is Silicon taken up
and transported in/to the plant (at a pH range ~ 7)
=4= As what/which compound is Si stored in the plant?
=5= and what function does the Si have in the plants?

[Edward Hennessey]

If someone is familiar with the Russian professional
literature,
this is one of its admirable specialties.
Regards,

What is your qualification to be an expert on Russian society?
We were
taught for all our lives that they were the enemy, only to find
out
later that they were just like us.

It seems to me that you ought to curse the politicians who lied
to you,
rather than the scientists.

Michael

Michael:

Whatever that missing link was saying, I didn't see until your
kind post because its prior incursions on our group had already
merited the killfile.
I do have a bit of that indicated Russian literature here and, if
time permits
someday, perhaps it will serve as grist for posting.

Regards,

Edward Hennessey

In sci.geo.geology, on Tue, 14 Mar 2006 11:54:18 +0100,
Carsten Troelsgaard sez:

I missed this earlier..

` General info on flint and chert
` http://www.abdn.ac.uk/geospatial/sum...factsheet1.htm

` Quote
` Cryptocrystalline Quartz

` Cryptocrystalline quartz is simply quartz whose crystals are so small that
` they can only be seen with the aid of a high-power microscope. It is formed
` geologically from silica that has dissolved from silicate materials. Over
` geological time, this amorphous silica gel dehydrates to form microscopic
` crystals and eventually becomes what we know physically as rock.
` Cryptocrystalline quartz occurs in many varieties. These varieties have been
` named based on their color, opacity, banding and other observable physical
` features. Technically speaking, the two varieties that account for the vast
` majority of "flint" artifact materials are chalcedony and chert.

` Other varieties encountered in the artifact world are agate, jasper and
` petrified wood. Interestingly, petrified wood is usually wood that has becn
` replaced by agate. This same process also occurs with coral, hence the term
` "agatized coral".

` Chalcedony Chert and Flint

` Chalcedony is a variety of cryptocrystalline quartz with extremely small
` crystals and a specific gravity (weight under water, a measure of a
` rock/mineral's purity) nearly identical to that of pure quartz. Due to its
` very high quartz content and super fine particle matrix, chalcedony has a
` very waxy luster.

Yipes, what a horrendously mangled misdefinition of specific gravity.
By that definition, water has a specific gravity of 0, and wood has
a negative sg. I guess it's a mistranslation of something from another
language, intended to be read as "weight divided by weight of an equal
volume of water", at least I hope that's the explanation.


--
================================================== ========================
Pete Vincent
Disclaimer: all I know I learned from reading Usenet.

a_plutonium writes:
wrote:
In article .com,
Farooq W wrote:

Dan wrote:

Soil and Dirt particles?! Is that a scientific analysis? Contaminated?

Dust and grit I'd reckon, too.

But I know some tree species evolved into a fire resistant bark in order
to live in fire prone regions, so I wonder what chemical it is that
gives them the best fire resistance. Is it potassium and salts?

Probably more to do with the structure of the bark. If it traps a lot
of air in bubbles (porous) or between layers of bark, the air will be
an effective insulator. A tightly rolled newspaper is difficult to
cleanly burn unless you can fan it strongly to burn away the charcoal
and blow away the ash as quickly as it forms, otherwise the powdery ash
smothers the flame. To wit, the Australian paper-bark tree is very fire
resistant, its bark being like a tightly rolled 1000-layer ricepaper
newsprint and contains no flammable resin.

Is a cork tree fireproof?
--
John Savage (my news address is not valid for email)

In article , Pete wrote:
` Chalcedony is a variety of cryptocrystalline quartz with extremely small
` crystals and a specific gravity (weight under water, a measure of a
` rock/mineral's purity) nearly identical to that of pure quartz. Due to its
` very high quartz content and super fine particle matrix, chalcedony has a
` very waxy luster.

Yipes, what a horrendously mangled misdefinition of specific gravity.
By that definition, water has a specific gravity of 0, and wood has
a negative sg. I guess it's a mistranslation of something from another
language,

Yuck.
Looking elsewhere ...
This large group includes all minerals with the primary chemical formula 5i02
(silicon dioxide) and is most abundantly represented in nature by pure quartz
and its many cryptocrystalline forms.

Now that looks like OCR gone wrong.

I don't recognise the names of the "maintainers" of the page, but looking around,
I think it's something maintained by the *geography* department. Can't expect them to
get rocks right. Or to walk straight while chewing gum.

I'll mention it next time I'm in the department. Or maybe I won't - I might be
asked to do the maintenance.

--
Aidan Karley FGS
Aberdeen, Scotland,
Location: 57°10'11" N, 02°08'43" W (sub-tropical Aberdeen), 0.021233

Aidan Karley wrote:
In article , Pete wrote:

` Chalcedony is a variety of cryptocrystalline quartz with extremely small
` crystals and a specific gravity (weight under water, a measure of a
` rock/mineral's purity) nearly identical to that of pure quartz. Due to its
` very high quartz content and super fine particle matrix, chalcedony has a
` very waxy luster.

Yipes, what a horrendously mangled misdefinition of specific gravity.
By that definition, water has a specific gravity of 0, and wood has
a negative sg. I guess it's a mistranslation of something from another
language,


Yuck.
Looking elsewhere ...

This large group includes all minerals with the primary chemical formula 5i02
(silicon dioxide) and is most abundantly represented in nature by pure quartz
and its many cryptocrystalline forms.


Now that looks like OCR gone wrong.

I don't recognise the names of the "maintainers" of the page, but looking around,
I think it's something maintained by the *geography* department. Can't expect them to
get rocks right. Or to walk straight while chewing gum.

I'll mention it next time I'm in the department. Or maybe I won't - I might be
asked to do the maintenance.

Bob wrote:
A Berkeley group is developing the use of a plant for Se
decontamination of soil. It is in field testing. (I could probably
find a ref if someone wants it.)

Then there are the Ni accumulators, which have several percent Ni in
their sap, nicely chelated (citrate, I think).

A.P. writes:
Bob, can you say anything theoretical about the periodic chart of
chemical elements as to that of fire, burning and ash. Consider that
the elements to making fire are oxygen, carbon which are far to the
right of the chart in rows 4A, 6A and that potassium of ashes is in row
1A far to the left in the chart. So is there some chart relationship as
to fire and burning and the ash remaining afterwards. Is the act of
fire some sort of acid base reaction.

Archimedes Plutonium
www.iw.net/~a_plutonium
whole entire Universe is just one big atom
where dots of the electron-dot-cloud are galaxies

Resuscitating an old thread, if anyone is still interested. This week's
Nature has an article that appears likely to be relevant :
http://www.nature.com/nature/journal...ture04590.html

In article _kIQf.196$Km6.54@trnddc01, Hanson wrote:
From: "hanson"
Newsgroups: sci.bio.botany,sci.chem,sci.geo.geology
Subject: Metals/Inorganics in Plants
Date: Sat, 11 Mar 2006 22:39:54 GMT

element or compound in tree bark that it burns with too much ash

"Bob" wrote in message
...
"Farooq W"
| More surprising the uptake of heavy metals especially
| Th and U by the plants...Barium is abnormally high or the
| soil on which that tree grew was rich in barium ores!

On Sat, 11 Mar 2006 02:27:31 GMT, "donald haarmann"
wrote:
The up take of uranium by plants is well know. See for example :-
Botanical Prospecting for Uranium on La Ventana Mesa, Sandoval
County New Mexico. US Geological Survey Bulletin 1009-M. 1956.
Some plants uptake serious amounts of selenium.

[Bob]
A Berkeley group is developing the use of a plant for Se
decontamination of soil. It is in field testing. (I could probably
find a ref if someone wants it.)
Then there are the Ni accumulators, which have several percent Ni in
their sap, nicely chelated (citrate, I think).
bob

[hanson]
=1= I posted this into sci.geo.geology in hope to get some views
from the geos' camp about the popularity & effectiveness of BP.
=2= As what/which compound does Si get into solution from the
calcogen silicates, considering that SiO4-- is stable only at
pH 11 in aq?
=3= in what soluble or sol-gel form is Silicon taken up
and transported in/to the plant (at a pH range ~ 7)
=4= As what/which compound is Si stored in the plant?
=5= and what function does the Si have in the plants?


Abstract:
Nature 440, 688-691 (30 March 2006) | doi:10.1038/nature04590; Received
5 September 2005; ; Accepted 18 January 2006
A silicon transporter in rice

Jian Feng Ma, Kazunori Tamai, Naoki Yamaji, Namiki Mitani, Saeko
Konishi, Maki Katsuhara, Masaji Ishiguro, Yoshiko Murata and Masahiro
Yano

Silicon is beneficial to plant growth and helps plants to overcome
abiotic and biotic stresses by preventing lodging (falling over) and
increasing resistance to pests and diseases, as well as other stresses.
Silicon is essential for high and sustainable production of rice, but
the molecular mechanism responsible for the uptake of silicon is
unknown. Here we describe the Low silicon rice 1 (Lsi1) gene, which
controls silicon accumulation in rice, a typical silicon-accumulating
plant. This gene belongs to the aquaporin family and is constitutively
expressed in the roots. Lsi1 is localized on the plasma membrane of the
distal side of both exodermis and endodermis cells, where casparian
strips are located. Suppression of Lsi1 expression resulted in reduced
silicon uptake. Furthermore, expression of Lsi1 in Xenopus oocytes
showed transport activity for silicon only. The identification of a
silicon transporter provides both an insight into the silicon uptake
system in plants, and a new strategy for producing crops with high
resistance to multiple stresses by genetic modification of the root's
silicon uptake capacity.

--
Aidan Karley, FGS
Aberdeen, Scotland,
Location: 57°10'11" N, 02°08'43" W (sub-tropical Aberdeen), 0.021233

Aidan Karley wrote:

I'll mention it next time I'm in the department. Or maybe I won't - I might be
asked to do the maintenance.

Why would you? You can't even manage your stuck capslock key. "or
maybe you won't", ... indeed. Somehow I don't think your very useful
around the house, Aidan.

Aidan Karley FGS
Aberdeen, Scotland,
Location: 57°10'11" N, 02°08'43" W (sub-tropical Aberdeen), 0.021233

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