Cheap and local source of Alum

[fibreweb]

Can anyone tell me if you can buy Alum ( Potassium Aluminium Sulfate) from anywhere other then a chemical supplier.
I have bought Copper Sulfate from the farm supplier and Sodium carbonate from the supermarket when it is just for junior use.

With 180 year 7 students we can go through over 2kg of Alum once they start doing crystals and at $22 for 500gms from Q stores that is just way too expensive.

Wendy

[Voice]

Science Supply Australia, Victoria, sell Alum at 3 kg for $48.00 if that helps Wendy.
Maree

[Lis]

Hi Wendy

I bought ours from Science Supply, 3kg $48, Chem Supply brand. We only use it for crystal growing, so I didnt think a cheaper one made a difference. I noticed Westlab have it too, 500g $18.90, buy 6 or more $17.20ea.

Cheers
Lisa

[RosalieM]

I think that is what farmers use to settle the dirt to the bottom of their tanks (they call it Alum, anyway... doesnt always mean it is the same thing!). Perhaps it would be worth checking out an agricultural supply shop? Eg Tamworth Rural or Furneys might be able to help you out.

[The Search Engine]

Hi Wendy!!

I bought a 25kg bag of alum from the local agricultural supply place and it would not grow decent crystals
So now I have a very heavy bag of useless material to take to the Ag Plot.

Cheers,

[Ocker]

Also try your local swimming pool shop!

[estelle]

I think there must be a difference in some of the quaility because some alum makes cloudy crystals and the other makes lovely clear ones.
So, I let them practice with the cheap stuff and for the students that are really keen they then get the dearer alum.
I have tried contacting someone at the nsw RACI to ask about the quality but all you get is an answering service promising to get back and she never does.
E.

[Rita]

Try your local chemist. Not sure of price. You mix it with warm water for a mouth wash.

Rita

[Ocker]

The main use of Alum, is as a floculent, you cast it on surface of water or wine, and as it sinks it grabs any particles,(cloudyness) bonds to them and takes them to bottom to be filtered out, leaving clear solution.