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darryl
12-16-2010, 12:03 AM
I grew some borax crystals awhile ago. Not large, just sparkly little bits on the ends of some strings. Look cool with leds shining on them- could be ok to hang on the tree.

Made me wonder yet again- can you affect the growth of a crystal by having a strong magnetic field crossing the 'growth zone'?

CCWKen
12-16-2010, 12:21 AM
Borax is a salt of Sodium and Boron. It might be possible if the field is strong enough. Boron isn't magnetic but Sodium is, sort of.

Evan
12-16-2010, 01:22 AM
It's fairly toxic. A gram or two will kill a cat. Sodium tetraborate (Borax) is slightly diamagnetic.

dockrat
12-16-2010, 02:12 AM
these are the biggest borax crystals you are ever likely to see

http://www.youtube.com/watch?v=co3jDaWzxUc

http://www.youtube.com/watch?v=6drrYFj91Ko

Edit... sorry ment to type gypsum crystals

darryl
12-16-2010, 03:43 AM
Well, right at the end of that video there was some disturbing news. After a harrowing, life threatening trek into the cave to retrieve the sample, they found it had grown- a whole millimeter after a year and a half.

Those are definitely some large crystals though. I always wanted to grow a good sized, basically flawless crystal of some kind. I don't know what I'd do with it- look at it from time to time I suppose.

vpt
12-16-2010, 08:41 AM
They are complaining about it being 122 degrees? That doesn't seam very life threatening to me.

jeremy13
12-16-2010, 12:35 PM
What do you expect there sciences. They work in a 65deF lab. They can come out to my shop in the summer. The un-insulated metallic roof radiates 150deF down at you. If you turn on the shop fan it's like being in a convection oven.

Black_Moons
12-16-2010, 01:36 PM
Yea I seem to recall borax is ant poisen. Definately NOT something to hang on the tree. Kids, Animals, etc. Also if one fell off and got steped on and ground into the carpet/flood, Not good.

Evan
12-16-2010, 02:46 PM
Boric Acid is ant poison and is a lot more toxic than Sodium tetraborate. Neither one should be where children or pets can get ahold of it.

aostling
12-16-2010, 04:00 PM
They are complaining about it being 122 degrees? That doesn't seam very life threatening to me.

The record high temperature for Phoenix is 122F (50C), occurring in June 1990. I didn't experience that, but I have hiked here when it was 119F. Any sort of exertion in temperatures this high is dangerous -- obviously the body needs sufficient water, but also salts and nutrients. I wouldn't go into that cave, but if I did I'd want to be out of it toot sweet.

2ManyHobbies
12-16-2010, 05:02 PM
They are complaining about it being 122 degrees? That doesn't seam very life threatening to me.
At 100% humidity? Check the heat index on that...
http://www.hpc.ncep.noaa.gov/html/heatindex.shtml

With 0-10% humidity, it is a completely different story.

Arcane
12-16-2010, 05:11 PM
It isn't just the high temperature, it's the high humidity combined with the high temperatures.

A heat index calculator (http://www.decatur.de/javascript/dew/index.html) gives 295 degrees when the temp is 120 and the RH is 80%.Another site (http://www.wrh.noaa.gov/lox/main.php?suite=safety&page=heat) gives it as 282 degrees. A third site (http://www.hpc.ncep.noaa.gov/html/heatindex.shtml) gives it as roughly the same.

Combine the super high heat index with the rugged going in the cave and it's easy to see just why it's considered so hazardous.

P.S. 2ManyHobbies, you beat me to it!

darryl
12-16-2010, 08:12 PM
Plus if someone falls, they might get diced, sliced- and that aint nice.

vpt
12-16-2010, 08:33 PM
Send in the robots!

Black_Moons
12-16-2010, 09:13 PM
Boric Acid is ant poison and is a lot more toxic than Sodium tetraborate. Neither one should be where children or pets can get ahold of it.

Isent boric acid what they say to add for eyewash?

Wiki says about boric acid 'Based on mammalian median lethal dose (LD50) rating of 2,660 mg/kg body mass, boric acid is poisonous if taken internally or inhaled in large quantities. However, it is generally considered to be not much more toxic than table salt.'

On borax it says:
Borax, sodium tetraborate decahydrate, is not acutely toxic.[13] Its LD50 (median lethal dose) score is tested at 2.66 g/kg in rats:

Weird, Exact same number. I wonder if they mixed the two up, Or if they are just that similar... They also mention borax is an ant poisen, and boric acid is also an ant poisen.
(Note, I know wiki is not 100% accurate, but its a good starting point, If you have URL's that contradict this information, I'll be happy to read them and consider them more accurate then wiki)

PS: 100% RH means that your body has basicly 0 evaporative cooling capacity, Hence no way to cool your body, And IIRC your brain cooks around 40c. So 50C + 100% RH = Your screwed without a jacket full of ice.

Fasttrack
12-16-2010, 09:32 PM
Darryl - to answer your original question: Absolutely!

It is a really neat "experiment", actually. You can get some really wild designs by applying electric or magnetic fields to the crystal growing apparatus. For instance, I helped a group of students with a project where they were growing copper sulfate crystals. They were actually working on making a program to do some fractal analysis of the crystal structure, but we had fun growing them. For instance, we seeded the solution with a copper wire and copper electrodes. By placing a potential across them, the crystals were all grown on the wire but with spokes towards the electrodes. Then, after placing a magnetic field over the apparatus, we made some spiral-arm galaxy like crystals. Actually pretty fun to do...

So I say ... try it and see what happens! Remember, if the potential is too high, the crystals will grow with many imperfections and be unstable. The slower you grow them the better.

Fasttrack
12-16-2010, 09:40 PM
Boric Acid: http://www.sciencelab.com/xMSDS-Boric_acid-9927105

Borax: http://www.sciencelab.com/msds.php?msdsId=9924967

Boric acid is more toxic than borax, but neither present enormous health concerns. Just treat it like you would any other potentially dangerous chemical.

Compare to Naval Jelly, something we are all familiar with.

http://www.henkelcamsds.com/pdf/235119_553472_Loctite_Naval_Jelly_01_%2080276_01_8 0277.pdf

It has a health hazard of 3 - more dangerous to health than boric acid.


EDIT: Nevertheless, I agree with the above. Not a good thing to have hanging on a Christmas tree! ;)

Fasttrack
12-16-2010, 09:43 PM
Borax is a salt of Sodium and Boron. It might be possible if the field is strong enough. Boron isn't magnetic but Sodium is, sort of.


The ion doesn't have to be magnetic. As they move in solution, the ion feels the Lorentz force (electric charges moving in a magnetic field feel a force perpindicular to their velocity). In the case of the experiment I mentioned, it is a trade off between forming a crystal slowly and still maintaining a high enough ion velocity to see a noticeable effect from the magnetic field. Essentially, the ions will start to rotate about the seed point and this net movement results in the spiral arms.

wierdscience
12-16-2010, 11:16 PM
Send in the robots!

In those conditions they don't work either.Read up what it did to they're camera and electronic equipment.

vincemulhollon
12-19-2010, 11:18 AM
Weird, Exact same number. I wonder if they mixed the two up, Or if they are just that similar...

Borax is the sodium salt of boric acid. Mix borax with hydrochloric (aka concrete etch?) and Borax's sodium ion runs off to elope with the chlorine ion from the hydrochloric, so you get watery table salt plus boric acid.

The molecular weight is high enough, and sodium is non-toxic enough, that adding or removing a sodium ion is only going to change the toxicity in about the second or third decimal place. Think of it being a bulk inert filler like sawdust in a loaf of bread. So they're close enough to be rounding error, although as usual, by weight out of a bottle the salt would be microscopically less toxic than the acid.

From decades old memory it tastes kind of icky, odorless and bitter. I suppose if you mixed a little into cheap tea for a long time you'd end up with chronic boron poisoning as I recall the body doesn't eliminate it terribly quickly. In the USA its illegal to add to food, but the rest of the world does add a little, I think in certain Asian dishes. Average lifetime consumption is probably much safer than, say, average lifetime mercury from fish consumption. Kind of like a "light" heavy metal.

From a HSM perspective, its well into the "wash yer hands after using" range but unless you're exposed 40 hrs/week at work or a 5 gallon bucket falls onto your noggin its very unlikely to kill you. The average HSM has way more dangerous stuff in their paint locker / glue shelf / anodizing-plating tanks. Its kinda bad, sorta, but if you are not the "wash yer hands before eating" type, then something more poisonous will almost certainly kill you before boron poisoning.

I'm only writing from memory and from a technical standpoint, if yer local govt demands you treat it as the most toxic of all toxic wastes, then you gotta do that, not because its bad but because the cops say so. Sadly that correlation is often screwed up for numerous other substances, not a unique problem of borax.

Signed, yer local ex-chemist.