how does one perform a recrystallization?
Borax purity grade
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That actually sounds kind of interesting. I like blue-green colors, and if you have to vomit, it might as well be pretty...
Another good quote from your source is this:
"However, boric acid poisoning is considerably rarer than in the past because the substance is no longer used as a disinfectant in nurseries. It is also no longer commonly used in medical preparations. Boric acid is an ingredient in some vaginal suppositories used for yeast infections, although this is NOT a standard treatment."
The part about the treatments of patients with open wounds shows an interesting aspect of boron poisoning. Healthy skin is a very good barrier to borax, but if you have open wounds it is readily absorbed into the body which can lead to poisoning.
well, I guess it's really cyan vomit
but anyway...how do you recrystallize Borax?
if it's simple...might be something fun to do with the box of Borax I have, but never use
here's an interesting bit of history:
http://www.letsgoseeit.com/index/county/inyo/death_valley/loc04/harmony.htm
but anyway...how do you recrystallize Borax?
if it's simple...might be something fun to do with the box of Borax I have, but never use
here's an interesting bit of history:
http://www.letsgoseeit.com/index/county/inyo/death_valley/loc04/harmony.htm
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Ole
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1) dissolve substance in water
2) allow water to evaporate.
Some substances need other solvents than water, but that's essentially it.
but....if you evaporate the water...don't the impurities just precipitate/recrystallize too?
Well, it sounds kind of just like it sounds. You dissolve the material in a solvent and make a saturated solution, borax into hot water in this case, and then let the water cool which creates a super-saturated solution. The material then drops out of solution, forming crystals. If this step is done slowly so that crystallization is selective, that's the step that "purifies" the material. It's a pretty basic procedure in chemistry. The contaminants are removed by simply separating the crystals from the solvent.
So by recrystallizing a material multiple times, you will eliminate some contaminants, things like the insoluble matter (i.e. dirt) that we discussed earlier will be removed, as will some other things. But it all depends on solubility of the contaminants and how selective/perfect the crystals can be grown.
It's interesting that you mentioned the Harmony Borax works at Death Valley. (I've been there, as well as to a really cool place in SE Oregon called Borax Lake - it has a thermally heated vent in the center of the lake so the water is warm even in the springtime, there are crystals of borax in the lake, really sharp crystals of borax, and a little fish called the Borax Lake Chub, which lives no where else on the planet except this lake. I've swam in it - I hear it has 50 times more arsenic in it than is allowed in drinking water, so I'm not sure which will kill me first, the arsenic or the borax. But Borax Lake had a borax mine there from the 1900-1910s and remains of the works can still be seen there.)
But back to the Harmony Borax works link - about half way down the page they mention that the borax produced there was crystallized twice to make two different grades of borax. From the web page:
"Workers heated water in the boiling tanks, using an adjacent steam boiler. Winching ore carts up the incline, they dumped the ore into the boiling tanks. Workers added carbonated soda. The borax dissolved, and the lime and mud settled out. They drew off the borax liquid into the cooling vats, where it crystallized on hanging metal rods. Lifting the rods out, they chipped off the now refined crystallized borax. To produce "concentrated" borax, they repeated the process."
Note the last sentence, "To produce "concentrated" borax, they repeated the process."
It's not so much that they were "concentrating" the borax as they were purifying it by recrystallizing it as I suggested above. I suspect that Pat's technical grade borax has gone through the exact process as described there. Just with a bit more modern equipment than mule power.
You're right, there is moisture in the air that can affect some materials. But at least I can be reasonably sure that I will not gaining insoluble matter, or chloride, or any other of the contaminants the one would be concerned with.
thanks
maybe I'll just end up using the borax as a flux next time I melt some brass..
re: alchemy...apparently the fluffy zinc oxide that forms on top of the molten brass was called "philosopher's wool"
maybe I'll just end up using the borax as a flux next time I melt some brass..
re: alchemy...apparently the fluffy zinc oxide that forms on top of the molten brass was called "philosopher's wool"
Pat, I always check any link that you give. Yes I read those MSDSs as well as one from JT Baker, a chemical supply house. That's what they say. So I ask you, did you read that paper that I linked to in the TSP thread on Borax? Here's a link to my post, (there was a url link here which no longer exists)
Pat, I hope you read it. It quoted a recent paper by the German Bundesinstitut für Risikobewertung, which review the current literature on borax and human toxicity. I think you will find it very interesting as there seems to be a big uncertainty as to the actual toxicity of borax. Sources vary widely. Acute toxicity does appear to be fairly large, as your MSDS's say, a teaspoon most likely will not outright kill you. From that paper, "No consistent data are available on the lethal dose of boric acid and borax in man (7). The pharmaceutical literature indicates 0.8 to 3.0 g for infants, 5-6 g for small children, 12 to 30 g for adults as the lethal doses after oral intoxication (4, 5)."
But it also goes on to say, "The tolerable upper intake level (UL) established by the European Food Safety Authority (EFSA) from all sources that does not lead to any health risks in conjunction with ongoing ingestion, is 10 mg for an adult per day."
That's quite a difference between 10 mg for an adult vs. 1/8th teaspoon, and I would hope anyone reading this would not attempt ingesting even a small amount like 1/8th teaspoon, even if over the course of the day. Why risk it?
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I read that paper before you posted it. Where did anyone get the idea that I was using or promoting the use of borax as medicine or food supplement? I simply mentioned, I guess in response to what I perceived as overblown estimates of the hazards of borax exposure. We get, from one source I read, that 10 mg per day from the air we breeathe and the water we drink. It is everywhere. I don't know how maany the French have killed or maimed by using borates as preservative.
This whole business started because I said 20 Mule Team Borax is good enough for Photo use. I have seen the list of impurities in the analytical grade that Mick Fagan bought, and the list of impurities in the product spec for Mule Crap is BETTER. I checked another source that claims high quality, Rose Mill, and Mule Crap is better than their's. The sodium tetraborate decahydrate from Rose Mill is guaranteed to have less than 10 ppm of SO4, less than 5 ppm of Cl and less than 5 ppm of Fe. The sodium tetraborate decahydrate from 20 Mule Team is guaranteed to have less than 3 ppm of SO4, less than 0.4 ppm of Cl and less than 2 ppm of Fe. No other impurities are mentioned in either product specification. The analytical reagent grade purchased by Mick Fagan has 50 ppm of sulphate, 100 ppm of Cl, and 5 ppm of Fe along with some other impurities that are not in the assay results from either Dial or Rose Mill.
It seems to me that the only argument we can make against MC is the variability in percent due to possible variations in the degree of hydration. Why hasn't one of our resident chemists suggested the time-honored cure for that problem--standard solutions?
If we make a saturated solution of whatever borax we have, whether it is the 5 mol or the 10 mol or a mixture of the two, the specific gravity of that solution will depend on the borate content, with a small error due to the impurities. At
http://www.borax.com/pdfs/dist/Profile_Borax_Decahydrate.pdf
You will find there, among other iteresting information, a table showing the percent of borax by weight in saturated borax solutions vs temperature. If you make a saturated solution of whatever borax you have at, say, 25 C (77 F) it will be saturated at any lower temperature with a concentration shown in the table. You do not need to weigh the borax or measure the volume of water initially. Add borax to water until some of it fails to dissolve. Decant enough of the clear liquid for your current needs. Add more water and borax to the stock as you use it so that it stays saturated. A saturated solution at 20 C contains 4.71 grams of borax decahydrate per 100 grams of solution. If you need 2 grams of borax to make an ultra accurate liter of D-76, weigh out 42.46 grams of that solution at 68 F.
If you are worried about the total 5.4 ppm of impurities in 20 Mule Team Borax, remember that is less than the 155 ppm of the analytical reagent grade purchased by Mick.
All I have to add is this:
if someone trademarks the name "Mule Crap Borax" ...I'll buy some
if someone trademarks the name "Mule Crap Borax" ...I'll buy some
Kirk;
The book "Borax to Boranes" discusses mining and purification much as you quote above. They also describe the alkaline springs with loads of borate salts in them and the locations WW. They are not specific as to purity grades as this was a text for chemists and chemistry students who either knew that data or knew how to look it up. It then goes on to quote more arcane chemistry such as synthesis of boranes for airplane and rocket fuels (something Patrick should know about) and the fact that Boron is one of the few elements that can produce Carbon chemistry analogs of organic chemicals. One example is Borazine (B3N3H6) which is an analog of Benzene down to melting point, dipole moment and boiling point. It decomposes in water however.
DE;
The green vomit is probably a mixture of bile with borate salts. Much the same can be seen when you dose yourself with Pepto Bismol (Bismuth salts). Bismuth interacts with bile and digestive juices to form a dark green mixture. But Bismuth is not poisonous as Borax is. Bismuth Salicylate and Bismuth Subnitrate are both used in Pepto Bismol and perhaps confusion with Borax is where this all came about.
Patrick;
You said originally about TSP :
"Originally Posted by gainer
Well, it is a laxative, but a teaspoon or more taken at one time can kill you. Some say 1/8 teaspoon in a liter of water drunk over the course of a day cures everything from constipation through dandruff to fibromyalgia and beyond. "
Which you then corrected to read:
"Now I see the ambiguity. I should have said I was referring to borax."
My reply, which has been verified is that this practice can cause death in children and a chronic illness in adults called "Borism" which has also been verified. It can also cause death in adults.
These taken together are entirely questionable statements of advice on your part and have prompted the subsequent posts in 2 threads regarding your advice and your understanding of the true nature of MSDS sheets. You have argued to the contrary of all reputable evendence that Borax injestion is rather harmless, when it is, in fact, not harmless at all.
PE
The book "Borax to Boranes" discusses mining and purification much as you quote above. They also describe the alkaline springs with loads of borate salts in them and the locations WW. They are not specific as to purity grades as this was a text for chemists and chemistry students who either knew that data or knew how to look it up. It then goes on to quote more arcane chemistry such as synthesis of boranes for airplane and rocket fuels (something Patrick should know about) and the fact that Boron is one of the few elements that can produce Carbon chemistry analogs of organic chemicals. One example is Borazine (B3N3H6) which is an analog of Benzene down to melting point, dipole moment and boiling point. It decomposes in water however.
DE;
The green vomit is probably a mixture of bile with borate salts. Much the same can be seen when you dose yourself with Pepto Bismol (Bismuth salts). Bismuth interacts with bile and digestive juices to form a dark green mixture. But Bismuth is not poisonous as Borax is. Bismuth Salicylate and Bismuth Subnitrate are both used in Pepto Bismol and perhaps confusion with Borax is where this all came about.
Patrick;
You said originally about TSP :
"Originally Posted by gainer
Well, it is a laxative, but a teaspoon or more taken at one time can kill you. Some say 1/8 teaspoon in a liter of water drunk over the course of a day cures everything from constipation through dandruff to fibromyalgia and beyond. "
Which you then corrected to read:
"Now I see the ambiguity. I should have said I was referring to borax."
My reply, which has been verified is that this practice can cause death in children and a chronic illness in adults called "Borism" which has also been verified. It can also cause death in adults.
These taken together are entirely questionable statements of advice on your part and have prompted the subsequent posts in 2 threads regarding your advice and your understanding of the true nature of MSDS sheets. You have argued to the contrary of all reputable evendence that Borax injestion is rather harmless, when it is, in fact, not harmless at all.
PE
To all;
Most chemicals used in photography will cake with time due to moisture from the air. They aggregate into lumps. This is most always the case with extremely pure chemicals that have the ability to absorb moisture out of the air.
Commercial grade chemicals have additives in them to prevent caking or lump formation. These chemicals include Borax, Sodium Carbonate, Sodium Bicarbonate and table salt. The anti caking agent is often either sodium silicate or talc (crushed dry rock used in talcum powder). But, it can be a variety of materials that either prevent caking or interact with moisture in place of the commercial material.
I am used to breaking up these cakes in our pure chemicals in my lab. With no extraneous material (photo or analytical grade) the chemicals would often cake, and so often a measure of purity is the degree to which a chemical cakes. Also, most chemicals are pure in color, and so brown sodium chloride is impure sodium chloride. Rock salt is an example.
So, the ability to cake and color can be applied as a guesstimate of purity. Look for snow white borax, salt, and sodium carbonate. Look at the labels for drying or anti-caking agents. All of these will dilute purity or add something potentially harmful to film but harmless to humans. One example is sand. Finely ground and sterile sand can be added as an anti-caking agent to foods. It is harmless and if fine enough will not affect a human, but will cause defects in film. Calcium Silicate, formed from Sodium Silicate in hard water can do something similar.
These tiny particles of insoluable matter can get into the gelatin and form minute specks or dots in prints. This is not removed by photo flo, nor can it be seen unless one makes large enlargements. That would be say 11x14 from 35mm or thereabouts.
So, impurities matter, but as I have said, use what works for you. OTOH, I consider my work to be important enough to deserve the best, so I use high grade chemicals and I measure them accurately. Remember, I said there can be both fun and serious work done in the darkroom. I use different methodologies and chemicals for each.
Also, remember that most chemicals are toxic to some extent or another. And remember that MSDS sheets are not always indicative of the true hazards.
PE
Most chemicals used in photography will cake with time due to moisture from the air. They aggregate into lumps. This is most always the case with extremely pure chemicals that have the ability to absorb moisture out of the air.
Commercial grade chemicals have additives in them to prevent caking or lump formation. These chemicals include Borax, Sodium Carbonate, Sodium Bicarbonate and table salt. The anti caking agent is often either sodium silicate or talc (crushed dry rock used in talcum powder). But, it can be a variety of materials that either prevent caking or interact with moisture in place of the commercial material.
I am used to breaking up these cakes in our pure chemicals in my lab. With no extraneous material (photo or analytical grade) the chemicals would often cake, and so often a measure of purity is the degree to which a chemical cakes. Also, most chemicals are pure in color, and so brown sodium chloride is impure sodium chloride. Rock salt is an example.
So, the ability to cake and color can be applied as a guesstimate of purity. Look for snow white borax, salt, and sodium carbonate. Look at the labels for drying or anti-caking agents. All of these will dilute purity or add something potentially harmful to film but harmless to humans. One example is sand. Finely ground and sterile sand can be added as an anti-caking agent to foods. It is harmless and if fine enough will not affect a human, but will cause defects in film. Calcium Silicate, formed from Sodium Silicate in hard water can do something similar.
These tiny particles of insoluable matter can get into the gelatin and form minute specks or dots in prints. This is not removed by photo flo, nor can it be seen unless one makes large enlargements. That would be say 11x14 from 35mm or thereabouts.
So, impurities matter, but as I have said, use what works for you. OTOH, I consider my work to be important enough to deserve the best, so I use high grade chemicals and I measure them accurately. Remember, I said there can be both fun and serious work done in the darkroom. I use different methodologies and chemicals for each.
Also, remember that most chemicals are toxic to some extent or another. And remember that MSDS sheets are not always indicative of the true hazards.
PE
thanks PE...I had no idea Pepto Bismol had Bismuth in it. It always amazes me how many different chemicals are all around us... Things that I had thought were difficult to find are often right under my nose once I read a few labels on things
I have a few chunks of Bismuth around here somewhere, but I don't think I'll eat them
I have a few chunks of Bismuth around here somewhere, but I don't think I'll eat them
Just another thought....
The pink dye in Pepto Bismol might add a green color to the digestive tract due to a pH change.
PE
The pink dye in Pepto Bismol might add a green color to the digestive tract due to a pH change.
PE
Pat - could you post a link to the product specs of the 20 Mule Team borax - I'm appearantly not smart enough to figure out how to seach the web with Acrobat.
Kirk
This would work - but you would need to pay attention that the saturated solution did not get supersaturated due to fluctuations in ambient temperature and have all the borax come crashing out of solution.
I actually prepare some reagents in the lab by having excess material in the bottom of the bottle and decanting what I need and then simply adding water to bring it back to volume for the next time I need it. It's a magnesium carbonate solution, which is not very soluble in water in the first place.
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My mistake. I thought you were intelligent enough to understand what I said. I did not in any way imply that I considered the ingestion of borax to be harmless. I did not advise anyone to ingest borax. I did quote a statement that I found in several of the MSDS for borax decahydrate: that accidental ingestion of as much as a teaspoon, about 4 grams, will not kill an adult.
You keep dancing around the original argument which dealt with the suitability of 20 Mule Team Borax for photographic purposes. I have quoted the guaranteed specs of that stuff, which specify that the impurities are guaranteed to be much less than those listed on the container of analytical grade borax that Mick Fagan got. I have noted that the variability of the percentage of sodium tetraborate decahydrate equivalent is probably due to the fact that some of the product is the pentahydrate. This kind of variability can cause one to get more anhydrous sodium tetraborate in a measurement by weight of powdered or granulated borax than is intended. I have pointed to the website where may be found a table of weights of borax decahydrate in saturated borax solution at temperatures from 0 to 100 C, which table may be used to calculate how much of a saturated solution of borax to weigh out in order to get the equivalent of a given weight of borax decahydrate in a solution. If you cannot see the logic of that, I pity you.
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First we'll work on the Acrobat problem. On the upper set of icons you see the search thingy that looks like binoculars. If you click on that, down in the lower right corner you should see a place to choose "Use Yahoo to search the internet". If you choose that, you have several alternatives above, where you can insert words to search for and choose to search for text or PDF files, etc. All this happens with Acrobat 7. If you don't have that version, you should be able to download it free.
Second, I have saved the data but not the link. A connection to www.borax.com should get you on the track. I'll go back and find it again and post the link later.
OK - here is it:
http://www.borax.com/pdfs/dist/Spec_Borax_SQ_Granular.pdf
Interesting that they don't mention insoluble matter or an equivalent description of dirt.
But Cl and SO4 does look good.
OK...so is this "Borax Decahydrate SQ Granular" the same Borax we get in the grocery store, or is it a different product?
Patrick;
This statement,
"Originally Posted by gainer
Well, it is a laxative, but a teaspoon or more taken at one time can kill you. Some say 1/8 teaspoon in a liter of water drunk over the course of a day cures everything from constipation through dandruff to fibromyalgia and beyond. "
which you seem to keep avoid acknowledging, is the one I refer to. As far as purity and toxicity, both Kirk and I have advised you to avoid using MSDS sheets for giving any advice on purity or toxicity.
Regarding purity, I have made myself clear in two previous posts about using chemicals of known purity and chemicals of unknown purity and the possibility of hidden bad contaminants. The fact that they are 'unknown' makes it impossible for me or anyone to report on them. I have also given my guidelines for using chemicals 'for fun' and for 'serious or professional work'.
Kirk states above that the borax and mud are separated in the purification process. Early fractions of borax, taken from crystallization ponds, can have silicates and Kirk states above that the URL you refer to does not relate to insoluable matter or dirt. Therefore your statement and that URL are meaningless in terms of a definition of utility in photoprocessing. I note again that powdered sand in suspension in any photo processing solution will be damaging to image quality.
I hope you are smart enough to understand this. And, I hope you also understand, if you read my posts, that when I'm wrong or give bad advice, I stand up and retract it myself either when I realize it is bad myself or when it is pointed out to me. You, OTOH, are doing a fancy tap dance around your own advice and also the comments that Kirk and I are posting here. I have answered your question and the OP as far as the information needed is known.
Several years ago, it took me quite a long time to convince you of the danger of heating organic solvents above their flash points when making developer concentrates. Do you remember that? And, I hope you remember how long it took you to change your recommendations for making up those developer concentrates. You never did acknowledge the danger inherent in your previous advice either, you merely changed your 'specifications' in a post.
PE
This statement,
"Originally Posted by gainer
Well, it is a laxative, but a teaspoon or more taken at one time can kill you. Some say 1/8 teaspoon in a liter of water drunk over the course of a day cures everything from constipation through dandruff to fibromyalgia and beyond. "
which you seem to keep avoid acknowledging, is the one I refer to. As far as purity and toxicity, both Kirk and I have advised you to avoid using MSDS sheets for giving any advice on purity or toxicity.
Regarding purity, I have made myself clear in two previous posts about using chemicals of known purity and chemicals of unknown purity and the possibility of hidden bad contaminants. The fact that they are 'unknown' makes it impossible for me or anyone to report on them. I have also given my guidelines for using chemicals 'for fun' and for 'serious or professional work'.
Kirk states above that the borax and mud are separated in the purification process. Early fractions of borax, taken from crystallization ponds, can have silicates and Kirk states above that the URL you refer to does not relate to insoluable matter or dirt. Therefore your statement and that URL are meaningless in terms of a definition of utility in photoprocessing. I note again that powdered sand in suspension in any photo processing solution will be damaging to image quality.
I hope you are smart enough to understand this. And, I hope you also understand, if you read my posts, that when I'm wrong or give bad advice, I stand up and retract it myself either when I realize it is bad myself or when it is pointed out to me. You, OTOH, are doing a fancy tap dance around your own advice and also the comments that Kirk and I are posting here. I have answered your question and the OP as far as the information needed is known.
Several years ago, it took me quite a long time to convince you of the danger of heating organic solvents above their flash points when making developer concentrates. Do you remember that? And, I hope you remember how long it took you to change your recommendations for making up those developer concentrates. You never did acknowledge the danger inherent in your previous advice either, you merely changed your 'specifications' in a post.
PE
I was considering the question again sitting here and have come up with a set of problems to illustrate this for you.
A photo grade chemical might be designated with a solids content of 1%, but the ANSI Photo Grade standard also defines the size of this particulate matter. And so, two chemicals with the same 1% impurity as solids but with two different sizes in that particulate matter might represent a pass and a fail of the ANSI standards.
The ACS grade often denotes halide presence as "total halide content", but for Photo Grade, the ANSI standards that we worked with gave each halide a percentage value. This therefore could classify the possible uses of chemicals for emulsion making only or for film emulsion only and etc. You see, Iodide content is critical in Sodium Chloride for a Chloro/Bromide, but much less so for a Bromo/Iodide.
Below a certain level, the halides present become rather unimportant for processing chemcials but above a certain level again the type of halide is critical for processing solutions.
Calcium and Potassium levels are of critical importance in fixes, and so a fixer must be free of those salts or it can be poisoned as a fixer. (See Mees and James or Haist on this one) They are not very important at all in developers except that a sloppy processor could carry too much developer with a Potassium salt into his fixer.
I hope this further clarifies this matter (if anyone is even reading this anymore).
PE
A photo grade chemical might be designated with a solids content of 1%, but the ANSI Photo Grade standard also defines the size of this particulate matter. And so, two chemicals with the same 1% impurity as solids but with two different sizes in that particulate matter might represent a pass and a fail of the ANSI standards.
The ACS grade often denotes halide presence as "total halide content", but for Photo Grade, the ANSI standards that we worked with gave each halide a percentage value. This therefore could classify the possible uses of chemicals for emulsion making only or for film emulsion only and etc. You see, Iodide content is critical in Sodium Chloride for a Chloro/Bromide, but much less so for a Bromo/Iodide.
Below a certain level, the halides present become rather unimportant for processing chemcials but above a certain level again the type of halide is critical for processing solutions.
Calcium and Potassium levels are of critical importance in fixes, and so a fixer must be free of those salts or it can be poisoned as a fixer. (See Mees and James or Haist on this one) They are not very important at all in developers except that a sloppy processor could carry too much developer with a Potassium salt into his fixer.
I hope this further clarifies this matter (if anyone is even reading this anymore).
PE
I'm still reading & learning
I have another example that starts with a hypothetical situation and then becomes more precise. It starts with the information that particle size has both an upper and lower limit. Above the high end, particles cannot get into an emulsion when swollen or can be filtered out, and below the limit the particles cannot be seen even at the highest magnification.
Lets assume for the hypothesis that Kodak Borax and 20 Mule Team Borax are the same and have 1% impurity and that is all clay and dirt. Lets also assume that Kodak's variety is 20% or more higher in price, so you buy the 20 Mule Team Borax. Now, what if that solid content is fine enough that it fails the ANSI standard for particle size? Kodak would then ball mill the product until the particle size was reduced to meet the ANSI standard for Photo Grade at the lowest limit which would allow the particle to be invisible. You see, you can grind a particle down to invisibility. This also raises the price, but also raises the quality of the finished image but at the same outwardly apparent grade.
Now, the real example. I know that Kodak did in fact ball mill several chemicals to meet their and the ANSI standards for particle size. I will not name the chemicals, but thats what actually happened. The ball milling turned the chemical(s) into Photo Grade.
This type of test is not often understood by non-chemists or non-photo engineers I'm sorry to say.
PE
Lets assume for the hypothesis that Kodak Borax and 20 Mule Team Borax are the same and have 1% impurity and that is all clay and dirt. Lets also assume that Kodak's variety is 20% or more higher in price, so you buy the 20 Mule Team Borax. Now, what if that solid content is fine enough that it fails the ANSI standard for particle size? Kodak would then ball mill the product until the particle size was reduced to meet the ANSI standard for Photo Grade at the lowest limit which would allow the particle to be invisible. You see, you can grind a particle down to invisibility. This also raises the price, but also raises the quality of the finished image but at the same outwardly apparent grade.
Now, the real example. I know that Kodak did in fact ball mill several chemicals to meet their and the ANSI standards for particle size. I will not name the chemicals, but thats what actually happened. The ball milling turned the chemical(s) into Photo Grade.
This type of test is not often understood by non-chemists or non-photo engineers I'm sorry to say.
PE
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