posted 01-12-2004 02:06 PM            

I have a child's tea set that is stamped
800 29PD any help would be appreciated.

My set is silver and it has been tested. The tea pot is 5½" to the top of the acorn style final. The sugar is 3½ to the top of the final. The creamer is 3".

Thanks
Bill

posted 01-16-2004 12:02 PM            

The 29PD identifies the region where it was made and the maker. The PD stands, I believe, for Padova (Padua) and the 29 would be the silversmith's individual registry number.

posted 01-16-2004 12:08 PM            

quote:

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What I do do on a plated item I look for a worn spot on the item and acid test it. If it is worn through it is usually plated.

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If you know it is plated, why even bother to look for worn spots? It you see it is worn through, why even bother to test it? What else could it be?

posted 01-16-2004 02:45 PM            

The acid does make a mark and/or leaves a spot. No matter how well one polishes out the spot, it doesn't change the fact that when any precious metal comes in contact with the acid the metal is now forever changed. The acid dissolves the surface of the precious metal. There is no way to replace that surface. At best the surface pitting can be polished to such a point that the spot isn't noticeable. But the abrasive polishing just removes more of the precious metal surface. Just because the damage is less noticeable it doesn't change the fact that the item tested and now polished is no longer the same as it was before testing.

Testing kits will tell you to use a file to get to the underlying metal. Once a file is used on the item it is even more damaged than just using the acid on the surface. Even when a person with the all the experience in the world does the acid test, they can not conclusively make an accurate determination by just putting acid on the surface. I can write (and have written) a book about this. But I won't go on and on. Nevertheless, here is one example:

Lets say you are pretty sure your item is solid silver. So you decide not to use a file to get to the underlying metal. You just want to determine whether the item is sterling or some other purity of solid silver. You put a drop of acid on a spot and your eye tells you that it is the reaction (color) for pure 99.9% silver. So what do you now know? Only that in your own opinion - the surface tested for 99.9% silver. This doesn't tell you anything conclusive about the item. You can now guess that the item has a pure coating of silver (99.9%) and so you suppose it must be silverplate. But the item could be sterling which has been silver plated (for matching color). If the item is silver plate then polishing the acid spot might cut through the last of the pure silver to reveal the base cooper. In an attempt to select an nu-obvious spot to test, you might have selected a part (i.e., a fitting or foot) that was silverplate but the rest of the object is solid silver. No matter what you decide, without further testing you still won't know with any more certainty. Continuing to do invasive acid testing just causes more damage.

Generally there are three different basic acids used; Nitric Acid, Aqua Regina, Dichromate Acid. Each of these can be formulated differently, each have different shelf lives, and in each the purity of the chemicals in the mix can be vastly different. Then there are the effects of temperature of the acid and of the object itself. Etc. Etc. Etc. The point is that when testing with acid there are many things that can effect the results. No one certifies the mixes and compounds of the acids, and the mixes don't come with expiation dates. So if the tester can't trust the acid then how can they trust there results of the test?

If a dealer is really a precious metal dealer then acid testing is a quick and easy way to make a best guess about what melting pot to throw item in.. On the other hand, if the dealer is an antique dealer then using acid is unnecessary and just damages and lessens the value of their inventory.