iandol on sun 21 dec 03
Dear Theresa Sandin,=20
To the best of my knowledge Cyanide is not used in the manufacture of =
Liquid Bright Gold Lustre. It can be used in the extraction of Gold from =
the rocks in which it is found.
During the processing of Gold to make a Lustre, metal it is converted =
into a salt using Aqua Regia, a concentrated mixture of Nitric and =
Hydrochloric acids which is the only acidic mixture in which Pure Gold =
will dissolve. The salt is then treated with Sulphur and Rosin to =
convert it into a resinous material called Gold Resinate. This is =
dissolved in organic solvents so that it will flow and can be used as a =
paint. One of the solvents used is Toluene. This is recognised as having =
carcinogenic activity. That is why you are instructed to use it in a =
well ventilated area and to leave the room where it is being fired.
I regard all heated waxes as potentially harmful. The vapours irritate =
my bronchial organs. When I do use a solid wax I choose Bees Wax. No oil =
or kero to dilute it. But you can get Aqueous Wax Emulsions which are =
just painted where you need the resist. Just keep away from the kiln =
during the preliminary heating phase when the resists burn away.
I think Jeff Zaking has written a lot about this sort of thing and =
published articles and the mags and published books about the whole =
deal.
Yes, it pays to be cautious. and you can do that without becoming =
paranoid if you do the research and ask questions to confirm the =
opinions you form for yourself. Some Silicone materials contain Strong =
Acetic Acid, much stronger than vinegar. It can irritate your nasal =
passages.
Hope you understand that !!
Best regards,
Ivor Lewis. Redhill, South Australia
John Rodgers on mon 22 dec 03
Ivor,
Interesting commentary on the processing of gold for use in ceramic
work. It concurs with what I have learned about gold as well. The
presentation of the information was well "spoken"!
As for waxes, I have used a variety of them but currently use parrafin
melted in an electric frying pan into which I dip my pot bottoms. Makes
a nice, even line. I am very careful not to get the wax hot enough to
smoke.
I also use an aqueous wax resist made by Duncan when I need a special
application. I particulary like the smoothness of the Duncan wax,
smoothness and ease of application with a brush, and the ease of
cleanup with hot water. Recent changes in their packaging has cause me
to begin searching for a replacement, but so far I have not found one.
It would be nice if I could make my own aqueous wax resist, but at this
point I haven't a clue as to how to begin.
Are you aware of any general aqueous wax resist recipes??
Regards,
John Rodgers
Chelsea, AL
iandol wrote:
>Dear Theresa Sandin,
>
>During the processing of Gold to make a Lustre, metal it is converted into a salt using Aqua Regia, a concentrated mixture of Nitric and Hydrochloric acids which is the only acidic mixture in which Pure Gold will dissolve. The salt is then treated with Sulphur and Rosin to convert it into a resinous material called Gold Resinate. This is dissolved in organic solvents so that it will flow and can be used as a paint. One of the solvents used is Toluene. This is recognised as having carcinogenic activity. That is why you are instructed to use it in a well ventilated area and to leave the room where it is being fired.
>
>I regard all heated waxes as potentially harmful. The vapours irritate my bronchial organs. When I do use a solid wax I choose Bees Wax. No oil or kero to dilute it. But you can get Aqueous Wax Emulsions which are just painted where you need the resist. Just keep away from the kiln during the preliminary heating phase when the resists burn away.
>
>I think Jeff Zaking has written a lot about this sort of thing and published articles and the mags and published books about the whole deal.
>
>Yes, it pays to be cautious. and you can do that without becoming paranoid if you do the research and ask questions to confirm the opinions you form for yourself. Some Silicone materials contain Strong Acetic Acid, much stronger than vinegar. It can irritate your nasal passages.
>
>Hope you understand that !!
>
>Best regards,
>Ivor Lewis. Redhill, South Australia
>
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iandol on tue 23 dec 03
Dear John Rodgers,=20
Thank you for your kind words on the Gold lustre part of the comment. =
Much appreciated.
Regarding Wax Emulsions, that is mixtures of Wax and Water, I have no =
recipe. Nothing in the notes I have from Conrad, "Contemporary Ceramic =
Techniques" was, I think the title of his book.
So it would be a case of going back to first principles. Since we are =
dealing with a wax whatever is made would need to be heated. So the =
choice of wax would be one with as low a melting point as possible. The =
second thing is to get the proportions right since heating will advance =
the rate of evaporation of the water. Our third problem is the choice of =
Emulsifier, the substance which will engage the hydrophilic reaction =
and neutralise the natural hydrophobic effects of water with wax. =
Finally, we might have to find a stabiliser which prevents premature =
separation.
Now, so you realise that this is not mere speculation I suggest the =
following experiment. Put a teaspoon of Water and a teaspoon of Olive =
Oil in a small glass jar. Shake and watch what happens. Now add a good =
pinch of Sodium Bicarb or Sodium Carbonate and shake again. My =
prediction is that in the first step the oil and water separate, in the =
second you will get a white fluid which will eventually separate.
When you have done this and have some ideas get back to me and I might =
have a little more information.
Culling on tue 23 dec 03
John - I use a cold wax, (water cleanup) that is used for silk screening.
Don't know who makes it But it's reasonably priced and my supplier in perth
always has it - food colouring added means I always know where I have waxed
too!
Steph
>Recent changes in their packaging has cause me
> to begin searching for a replacement, but so far I have not found one.<
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