Patina on brass.

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Kittyhawk

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I have a little bottle of fluid that turns brass, bronze, copper and to a much lesser extent aluminum very dark when applied to the surface with a brush, left for a few minutes and then wiped off.
Had it for years and the problem is the label has come off, I need some more and I can't remember what it is. Can anyone help please?
 
Sounds like Tourmaline

https://www.ebay.co.uk/itm/324109126158
Cheers
Peter
What is it exactly? I've just been trying to remove the dark surface of a brass door handle, with a buffing wheel and the black wax stuff, but beginning to think it's a deliberately applied finish and hard to remove. I've given up and left it with just a few shiny high-lights. :rolleyes:
PS it's on the label in the link!
 
Sounds like Tourmaline
Interesting. We are installing new lights at the moment that are an antique brass style. We have found a light we like for over our kitchen peninsula but it only comes in black or bright shiny brass. Looks like I could use this to give the light the antique feel of the others

Sean
 
I've used this on screws and screw cups in a listed manor house, they had a leak under the floor that had cupped the floor board really badly. We managed to kerf the back of the board and persuaded it to go back flat with brass screws. But the bright screws looked so out of place and just glared in your face when you walked into the room.

We used the antiquing fluid to 'age' the screws and it looked like it had been done a 100 years ago like the rest of the floor. I would highly recommend this product.
 
I should have added - the fluid is in a medicine bottle and I have a vague recollection I bought it at a pharmacy on someone's advice..
 
I have used ammonia .88 added to mahogany sawdust in a sealable plastic container, the item is laid in the box and sealed (ammonia smell is unpleasant!), inspected regularly, then wash off at the stage you want. Usually a light buff up with polish to seal and give it a bit of shine. I would also add that most brass items will be lacquered, which will need to be removed prior to any treatment. I have used Liberon's Tourmaline but have never felt that it looks as natural as the above method, which I have used for over 40 years.
 
I should have added - the fluid is in a medicine bottle and I have a vague recollection I bought it at a pharmacy on someone's advice..
Copper sulphate solution????

EDIT Just come across a great site - sciencecompany .com/Patina Formulas for Brass Bronze and Copper
 
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I have used ammonia .88 added to mahogany sawdust in a sealable plastic container, the item is laid in the box and sealed (ammonia smell is unpleasant!), inspected regularly, then wash off at the stage you want. Usually a light buff up with polish to seal and give it a bit of shine. I would also add that most brass items will be lacquered, which will need to be removed prior to any treatment. I have used Liberon's Tourmaline but have never felt that it looks as natural as the above method, which I have used for over 40 years.
Whilst at Art College a friend would try and persuade us to 'wee' on his bronze casts, to add a little patina. But,when nature called, it was always too much of a detour to go by way of the outside sculpture yard. :) So I can see how ammonia would work quite well.
 
Nothing to do with the fluid and possibly a dumb point - are you sure your proposed purchase is actually brass (much these days is plastic or coated) and not already lacquered.
 
Nobody seems to be giving the info you're looking for except the reference to tormeline and aging liquid. What you are describing sound like an acid of sorts - which would tarnish (blacken) some metals. Someone in a lab with a GC or spectrometer will be able to tell you what it is. If in doubt, treat it as hazardous and dispose accordingly.
 
No, he clearly wishes to use this solution for the job he remembers he used it for in the past! I agree if there is any left, dispose of it safely and use either tourmaline or ammonia mixed with sawdust as suggested.
 
I've used tourmaline in the past to age new Carlisle brand door hardware, what is a real pain is getting whatever varnish the factory applies - it takes 2-3 coats of whatever passes for nitromors these days...
One other thing, having antique'd your piece to taste you need to protect the finish with jade oil, which is one of those dries by oxidation oils and produces a really tough finish that will take years of use, by which time the underlying brass looks pretty old anyhow. Here is my workshop doorhandle that gets pretty frequent use -
20230103_144626.jpg
 
Nothing to do with the fluid and possibly a dumb point - are you sure your proposed purchase is actually brass (much these days is plastic or coated) and not already lacquered.
In the aircraftery I use 0.2mm brass sheet and bronze brazing rod to fabricate little bits and pieces for the model aeroplanes.
I've been online and seen that I can buy tourmaline here in NZ, it's the 40 bucks for a wee bottle and $7 courier fee that's making me choke on my coffee. Going to try a few home remedies as per above posts if I can't remember what the stuff in my bottle is. Don't think my clients would be best pleased if they knew I was peeing on bits of their models though. Rather reminds me of the ancient practice of corning gunpowder to increase its power and this was done by peeing on the powder before regrinding - and bishop's urine was the preferred option. Sounds like nonsense but apparently bishop wee was more effective because they were in the habit of guzzling a lot of wine. Good excuse to try that.
 
In the aircraftery I use 0.2mm brass sheet and bronze brazing rod to fabricate little bits and pieces for the model aeroplanes.
I've been online and seen that I can buy tourmaline here in NZ, it's the 40 bucks for a wee bottle and $7 courier fee that's making me choke on my coffee. Going to try a few home remedies as per above posts if I can't remember what the stuff in my bottle is. Don't think my clients would be best pleased if they knew I was peeing on bits of their models though. Rather reminds me of the ancient practice of corning gunpowder to increase its power and this was done by peeing on the powder before regrinding - and bishop's urine was the preferred option. Sounds like nonsense but apparently bishop wee was more effective because they were in the habit of guzzling a lot of wine. Good excuse to try that.
Interesting that you braze sheet that thin, I have never really considered it. Is there any specific reason not to solder, I would have thought it easier for such thin sheet. Would love to know how you go about it and what rods you use.
 
I've used tourmaline in the past to age new Carlisle brand door hardware, what is a real pain is getting whatever varnish the factory applies - it takes 2-3 coats of whatever passes for nitromors these days...
One other thing, having antique'd your piece to taste you need to protect the finish with jade oil, which is one of those dries by oxidation oils and produces a really tough finish that will take years of use, by which time the underlying brass looks pretty old anyhow. Here is my workshop doorhandle that gets pretty frequent use -
View attachment 150385
Clear shellac is also good, for indoor stuff anyway, and easily removed if you need to.
 
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