I speak from experience when I say that it can be hard to tell a nickel-lined copper pot from a steel-lined one.
I got into a heated argument on Chowhound over this. I insisted a particular pot of mine was lined with stainless steel but I was dead wrong: it was nickel. I was absolutely sure I was right because to my eye it looked just exactly, exactly like steel. I am embarrassed to have been so adamant when I was in the wrong, and I told myself I’d learn more about nickel and steel so that I could avoid this mistake in the future. (Reining in my ego is a separate challenge!)
One comforting realization is that at least I’m not alone: many people seem to make the same mistake. I’ve seen multiple eBay and Etsy item listings for copper pots described as tin- or steel-lined that I suspect are nickel-lined. I don’t think it’s necessarily malicious on the part of the seller, because they can be difficult to distinguish from each other, and ultimately the pots will perform similarly.
But it’s good to know which lining you have because nickel needs to be treated more like tin — no metal utensils, no hard scrubbing — while steel can withstand rougher handling. I’d like to share with you what I’ve learned in hopes that it will help you to be a more informed buyer.
Typically Nickel will have a more silver look, while chrome will have a high shine.
Is it nickel or is it chrome? Older pieces, especially those produced before the 1930s, are more likely to be nickel than chrome. Wagner used only nickel. Griswold plated its earlier pieces in nickel, but switched to chrome at about the beginning of the “large block” TM era. Nickel-plated pieces usually exhibit a warmer, yellowish tone whereas chrome (chromium) gives a colder, bluish impression. Nickel is often finished only to a soft luster; chrome typically to a high, mirror-like polish, if not left satin/matte.
Manufacturers early on realized there was a segment of the market that desired the features of cast iron cookware, but perhaps did not care for its rustic appearance or the maintenance it required. One of the first ways makers addressed this issue was to offer plated versions, first in a nickel finish, and later in chromium. Nickel-plated pieces are known from as early as the 1890s, with manufacturers seen moving to chromium in the 1930s.
The question often arises regarding the removal of plating from worn pieces in order to leave them bare iron. While nickeled pieces in general appear simply to be plated versions of their plain iron counterparts, chromed pieces, where a mirror finish was desired, were first machine-polished smooth. De-plated chromed pieces will therefore not be the same as the versions originally produced as bare iron.
Although pieces were plated inside and out, many of those seen give the impression of having been made leaving the cooking surface bare iron. It appears, however, that typical wear was simply consistent enough to make that inference. If true, the application of a substance would have been necessary to prevent the plating adhering to selected areas, but it would have required something that could withstand the high temperatures and acidic environment of the plating process. NOS (new old stock) pans with labels as well as catalog verbiage (“nickel plated finishes inside and out”) confirm cookware plating was an all-over process.
Wagner was only known to have plated with nickel, although a popular guide book claims the use of chrome in the 1940s-1950s. Wagner catalogs from the 1924 and 1927 feature sections of nickel-plated wares with catalog numbers different from those of their bare iron counterparts. Empirical observation, however, reveals that the nickel-plated items physically bore the same catalog numbers as those of the bare iron.
Stainless steel as a lining for copper pots
Stainless steel is an alloy of iron, chrome, and nickel. Each of these component metals bonds differently to copper — nickel rather well, but iron and chrome not very easily. This makes it difficult to get steel to adhere to copper without some kind of intervention.
In the early 1970s, US manufacturers such as All-Clad were bringing sophisticated multi-ply steel pans to market using advanced techniques to bond, shape, and finish clad cookware, and French manufacturers had to compete. In the 1970s, the Belgian cookware firm Falk Culinair developed and patented a process to bond sheets of copper and steel into “copper bimetal”: 2.3mm of copper and .2mm of steel for a total thickness of 2.5mm. Falk found a German sheet metal supplier to mass-produce bimetal sheets and in 1983 released a line of steel-lined copper cookware.
Others quickly followed suit. In 1989, Mauviel began manufacturing Cuprinox, their own line of steel-lined pans. (They used the Cuprinox name until circa 2007 when they switched to the M’150/ M’250 nomenclature.) Other French manufacturers including Atelier du Cuivre, Havard, and De Buyer began making stainless-steel lined pans in the 1980s and continue to this day.
Stainless steel linings for pots come in brushed, mirror, or matte finishes depending on the copper bimetal stock and how the pan interior is polished at the factory. Steel withstands high cooking temperatures (Mauviel rates its steel-lined pans to 500°F/260°C) and its hardness means that even the .2mm in a typical pan lining will tolerate metal cooking utensils and hard scrubbing with no more than a few surface scratches.
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FAQ
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