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What is "Italian silver"
November 17, 2009
Is there such a thing as Italian silver? If yes, what is its difference to sterling silver? I'm thinking of buying Italian silver earrings from a friend and just want to know if it will wear off/rust or stain. Thanks!Pamela Buenafe
buyer - Philippines
November 19, 2009
I have been collecting silver pieces for years and I can safely tell you that there is probably an Antarctic fine silver being advertised some where.
Silver in its purest form is like gold and is impervious to tarnishing. Unfortunately silver is so soft that it can not be used in its pure form. It is alloyed with any number of other elements to bring up its hardness to a point where it can be used for jewelry or flatware. All of the silver that we use does tarnish but just at varying rates.
The most common cause of tarnish in silver is the use of copper. Copper has real love of some acids, oxygen and sulfur and likes to borrow these atoms almost at the drop of a hat which gives us the lovely black patina that we like to call tarnish.
The different forms of silver such as English for example are just an alloy that is unique to a specific area. As a rule they all have the same different elements in the alloys but only in slightly different amounts. But even alloys made in the same area can differ widely from one silver smith to another. You might buy one alloy in one shop and then walk across the street and get a totally different alloy.
The only constant that you find in specific areas is in the design of the finished pieces. Styles become vogue in certain areas and over a period of time all of the makers in a given area will begin making basically the same looking product with of course slight variations to style which fit the silver smiths individual taste, skill or lack of it. Let's face it, whatever is in style sells and what ever sells will be produced it's the basic law of business.
The only semi true constants in alloys are the 3 basic alloys. Fine silver which ideally is 99% silver. Sterling silver which is ideally around 92% silver and Britannia silver which is 96% silver.
The best advice that I can give you with silver is to buy something that looks nice on you or something that you like. Buy stuff made from sterling if possible so that it will wear well and just live with the fact that you have to polish it once in a while. Besides jewelry is more or less toys for girls and polishing, maintaining and playing with it is half the fun!
November 22, 2009
I HAVE A COMPLETE SET OF DINNER WARE, ALL THE UTENSILS ARE MARKED
HOW MUCH SILVER IS IN THE ALLOY?
WERE THESE UTENSILS MADE IN PANAMA?
COLLECTOR - HICKSVILLE, New York
November 22, 2009
Hi, James. I believe there is no silver in "Panama Silver", based on an eBay guide on the subject.
Ted Mooney, P.E. RET
Pine Beach, New Jersey
November 28, 2009
Panama silver is slang. As is crup-nicole, Cupernickel or Coppernickel. The proper name for panama silver and all these slang words is Cupronickel.
In days gone by it was rather popular for bullet jackets in Europe. Americans were not fond of the crup-nicole as the jackets could shatter at high velocities.
Bullets are designed to expand due to centrifugal force not by being smashed or crushed as is commonly believed. As an example a bullet from a 220 Swift spins at approximately 240,000 RPM. A pure lead bullet would simply turn to dust at those RPMs so a jacket is used to hold it together. The jacket is thin at the front and gets progressively thicker as it moves toward the base. If the jacket is torn or upset the kinetic energy in the rotating core causes the bullet to open up laterally and then push rearward as it push's though the target to form the traditional mushroom shape.
Although it is not particularly hard, Cupronickel does not handle shock all that well and like cast iron can shatter. It is still widely used in musical instruments such as drums, flutes and clarinets and also in some marine applications where salt is an issue.
For a time it was a common form of fake silver in flatware. If you put a silver fork next to a Cupronickel fork you can almost immediately see that they don't look the same. Most of the time the Cupronickel will have a very slight yellow tinge to it. Some people claim they can taste Cupronickel. I'm not one of them but they claim it tastes bitter or dry. Whether it's in their head or not I don't know. I have often tried to detect a taste but I get nothing.
Cupronickel jacket material is basically a mix of 3 parts copper and 1 part nickel but can contain manganese, iron and spelter. Cupronickel flatware is sometimes silver plated in an effort to fool fools I should think. Cupronickel is magnetic so there is no reason to be fooled! Even if it is silver plated, I would bet there is less than $5.00 worth of silver in a full Cupronickel flatware set!
+++++December 2, 2009 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread
I bought a set of (what I guess to be) silver plated flatware, marked "Davco Silver China". What is the metallurgical composition of this material?
I had one piece that was an "odd" or extra of the set, so I used silver testing solution on it and it turned gray! I then tossed it into a crucible and melted it; It melted readily (and still showed up a gray instead of burgundy sort of color that sterling silver shows up as with silver testing solution). What sort of "filler" material was/is used with this stuff? It melts easily and is a bright silvery color.
learning about metallurgy - Beachwood, NJ USA
First of two simultaneous responses -- December 2, 2009
I have seen the stuff that you are talking about. Its not so much a type of material but an import company. http://www.davcosilverltd.com/ I have seen some pieces that were used that had some scratches in them and it showed copper under the scratches which obviously would be the base plating I suppose. I never really did take a close look at it as a complete cutlery set sells for under $100.00, new for what looked like a gazillion pieces so it really wasn't something I was particularly interested in. Because of the light weight I sort of felt that it was a cheap grade of steel that had been silver plated but if you say it melted with ease I would suppose that it would have to be tin which melts at 450 degrees or something similar. Cupronickel melts at around 1200 degrees. I never did try to put a magnet to it and Cupronickel would actually be sort of to expensive to use on the Davco stuff that I have seen.
Second of two simultaneous responses -- December 3, 2009
I forgot to add and should have that it is non-magnetic. I can find little or no information on "Davco Silver China" specifically pertaining to it's manufacturing or composition anywhere.Gavin Gist
- Beachwood, NJ, USA