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Some folks recommend Hagerty's; I use this stuff:



The polishing ingredient is rouge; it doesn't stink and leaves behind a protective wax coat that works very well. Get it at auto parts stores.

http://www.maasinc.com/products_metalpolish.html

tubafreaks7 wrote:Anyone know if using tarnX is harmful? I just put it in a spray bottle, stick the horn in the tub and do a small area of the horn at a time rinsing as I go.

TarnX is basically thiourea in an acid solution with some detergent to aid wetting.

Thiorurea is a suspected carcinogen, so wear gloves and eye protection. It's also the prefered method for cleaning museum silver, since it dissolves the silver sulfide tarnish rather than abrades it off. OTOH, TarnX will do nothing to disguise scratches, where a mild abrasive like rouge or chalk will smooth our their appearance somewhat.

See:

http://householdproducts.nlm.nih.gov/cg ... d=10006001
http://palimpsest.stanford.edu/waac/wn/ ... 1-103.html

The biggest factor of how fast a silver horn will tarnish is how much sulfur is in the air where the horn is stored. I have a big problem during the winter because I use a ventless gas fireplace in my music room. Sulfur is a by-product of a gas flame. I am sure there are some products out there that will slow down the tarnishing process but, in my opinion, the only REAL to deal with the problem is to keep the horn in a tight case or store it in a plastic bag.

tubafreaks7 wrote:What can I do to keep an old silver horn from turning black? . . . .

I'll put in my standard plug to spray with lemon Pledge furniture polish after getting a good shine. The thin layer of oil in Pledge will prevent tarnish from sulphur and other active elements in the air. Use an old t-shirt to wipe off the excess.
You can also make a preserving cover or sack, using silver-protecting fabric.

A recent discovery at a department store was Hagerty's spray polish. It's basically the same as mentioned above, but since it's in spray form it's easy to get it into those bends and nooks that can be a pain to polish. You simply spray it on, wait a minute, and wipe it off with outstanding results.

All polishing, to some degree, takes off metal, albeit a microscopic amount, because the tarnish is, among other things, sulphur that has reacted with the silver.

One way to get some of the silver back before you polish is to put the horn in a large non-reactive container (plastic or enameled, even a bathtub if necessary) that you can totally immerse the instrument, line the bottom with plain aluminum foil, set the instrument on the horn, add about a cup of sodium carbonate (washing soda, NOT bicarbonate -- baking soda) and pour boiling water over everything. The carbonate acts as a catalyst to the sulphur, which is more reactive to aluminum than to silver. It will bubble like a witches' brew, as the sulphur ions leave the silver and attach to the aluminum, with the result the silver redeposits on the horn and the aluminum is consumed by the sulphur. After it quits bubbling (this could take awhile, like hours) clean and rinse the horn in the usual manner, then polish softly.

I've done this on an old euphonium that was almost beyond hope, and got some decent results. Not perfect like a new plate job, but enough that it again made polishing worthwhile.

iiipopes wrote:One way to get some of the silver back before you polish is to put the horn in a large non-reactive container (plastic or enameled, even a bathtub if necessary) that you can totally immerse the instrument, line the bottom with plain aluminum foil, set the instrument on the horn, add about a cup of sodium carbonate (washing soda, NOT bicarbonate -- baking soda) and pour boiling water over everything. The carbonate acts as a catalyst to the sulphur, which is more reactive to aluminum than to silver. It will bubble like a witches' brew, as the sulphur ions leave the silver and attach to the aluminum, with the result the silver redeposits on the horn and the aluminum is consumed by the sulphur. After it quits bubbling (this could take awhile, like hours) clean and rinse the horn in the usual manner, then polish softly..

This isn't a bad process and one that's been known to Heloise aficionados for quite some time.

Let's be very clear here as to what causes the bubbling. It's the liberation of hydrogen as the aluminum combines with the very basic hydrolized sodium carbonate. (It's also why the bubbling doesn't stop when you take your horn out of the solution).

If the sulfur really manages to combine with the aluminum, it isn't for long--aluminum sulfide readily hydrolizes in an alkaline solution to produce the hydroxide with the liberation of hydrogen sulfide gas (hence, the rotten egg smell).

Washing soda, borax or TSP will work about equally as well. You could also do this in cold water using a lye solution. Zinc will work as well as aluminum.

But do this in a well-ventilated area--hydrogen is explosive in a very wide range of mixtures. And hydrogen sulfide is as poisonous as carbon monoxide if inhaled.

Regardless of the ingredients used, you'll still need to polish if you want a shiny finish.

Here's a page on silver conservation:

http://nautarch.tamu.edu/class/anth605/ ... m#GALVANIC