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Thread: Chromium Oxide 1.0?
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07-21-2009, 09:49 PM #11
ok lets try a little different way.
example .
CO2. HAS weight 1 kg.
now we can get CO2 IN many different ways right? burning,chemical reactions etc etc.
and we get get in in different countries example
usa gets it by chemical way
Russia by burning woods etc etc.
end result is CO2
right. CO2 never changes still same CO2.
Now you can mix is with different helium etc gases and get a little lighter or heavier gas but clean CO2 WILL be always CO2.
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07-21-2009, 11:31 PM #12
Hmm, Oxygen is O2 but there's O3 and O5 too. And what about heavy water?
The ore for chrome is Chromite which is Cr2O4 with added iron and magnesium depending on purity.
Most chrome oxide is made for lapidary work so it can be ground to different grits according to need no different than alumina is.
I don't see any reason why the formula can't be artificially adjusted no different than iron oxide has several variants as long as the compound is stable and will bond together.No matter how many men you kill you can't kill your successor-Emperor Nero
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07-23-2009, 02:24 PM #13
I would assume that .5 microns refers to the size of a single molecule of CR2O3 (two chromium atoms and three oxygen atoms).. which I intuitively agree with hi_bud_gl that it would always remain constant.
I guess this would leave the rest up to level of purity?
I've come across some chromium oxide on the internet, being sold for cosmetic value - as a green pigment. Though I have already arranged with Chris for him to send me some of his, I'm curious how pure this cosmetic chromium oxide would be, just as a general rule. I mean, it does say "chromium oxide"... I wonder if it would be 0.5 microns as well.
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07-23-2009, 02:38 PM #14
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07-23-2009, 04:46 PM #15
I will jump in here, being a chemist I am sorry I have to disagree with you Hi-bud-gl,
I hope yo don´t take offense.
Chromium Oxide (ie Cr2O3) is the name of a pigment that is green in color.
Like ANY other pigment or cristalline structure there are many, literally infinately many variations
depending on how much time the crystalls had to bind each other
and some other variables like temperature and pressure I guess.
That´s why one could think of a single chromium oxide piece as big as the hope diamond.
Cr2O3 is a bad example for this, but how about Alumoxyde.
Al2O3 is available in any grit size, even as big as a palm
in the form of jade!
Believe me the molecular size of Cr2O3 is WAAAAAAAAAY smaller than 0.5 micron.
Cr2O3 has been commonly used as polishing compounds before,
that´s why 0.3 to 0.5 micron particles were mainly produced.
But if you buy some chromium oxide you don´t have a clue what grain size it actually has!
That´s why we in germany use Lukas Acrylic Color with the Pigment PG17 (wich is Cr2o3),
it definitly has a grain size of 0.3 to 0.5 micron.
There are however many other grain sizes like 12 micron.
btw: this can not be solved by adding or taking some elements out of the compund.
Cr2O3 is Cr2O3 or its not our chromium oxide.
Being crystalline however we "could" say (Cr2O3)n
n being the number of molecules in one cluster.
But still this would not lead anywhere.
but to answer the original question: I don´t know of any source for chromium oxide
in 1 micron.
You should go for Al2O3 or DiamondLast edited by Lesslemming; 07-23-2009 at 04:49 PM.
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07-23-2009, 05:01 PM #16
You can get 1.0 micron Chrome Ox from here Polishing Suspensions - Extec®
Kindest regards,
Alex
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07-23-2009, 05:03 PM #17
Ok that's interesting... so for chromium oxide used for pigmenting in paints or for cosmetics, we really have no idea what size those "clusters" are?
They may very well be not 0.5 microns?
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07-23-2009, 05:04 PM #18"Blues fallin' down like hail." Robert Johnson
"Aw, Pretty Boy, can't you show me nuthin but surrender?" Patti Smith
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07-23-2009, 05:10 PM #19
Interesting i think i am shocked or there is some misunderstanding.
I will type this again. As you are chemist Please let me know you understand what i am saying. I told early
Cr2O3 doesn't matter you make from it pigment ,stone ,water or glue or get it from mountain or dirty water in usa or in Germany is = Cr2O3 will not change it is size ,weight etc etc. it is permanent.
if you are against this Then explain to me what is a differences between GErman and Usa made Sugar. in chemical forms.
i would appreciate
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07-23-2009, 05:18 PM #20
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Thanked: 317It's also used as a pigment in ceramic glazes. I can't remember what color it turns after firing off the come of my head. I want to say it turns pink in a reduction kiln and yellow in an oxidizing kiln, but it's bee so long since I did any pottery that I'm probably completely wrong..