Trio of pans "Edmond James de Rothschild"

How I define collectibility

This is a subjective concept. I define “collectibility” as durable appeal to a majority of people who are interested in buying copper. I don’t have direct data on what buyers want, but I watch listings and prices and I have my own experience as a collector and user of copper.

Disclaimers and caveats: I am not an appraiser. I do not buy copper as a speculative financial investment. This is not investment advice. I make no claim that any purchase based on my advice will increase in value.

But based on what I see and my experience with copper I’ve bought and used, these are the factors I consider to be elements of a piece’s collectibility.

  • Thickness
  • Quality
  • Condition
  • Provenance
  • Rarity
  • Usability

I think of these as factors as part of a scoring system: no one factor can overwhelm all the others. A piece might score high in some areas and low in others and still be highly collectible, because each collector has different priorities. For example, I might overlook damage (bad score for condition) in a piece made by a coppersmith I love (high score for provenance) because that’s the kind of collector I am. Another collector looking to build a world-class batterie de cuisine would care far more for thickness and condition, but not give a fig for the provenance.

But chances are that pieces that score well across multiple factors are likely to find a receptive buyer, and that’s the definition of collectibility for me. So in that spirit, I offer my opinions below.


In my opinion, the thicker a piece of copper cookware, the greater its collectibility. Copper thickness is the single most important factor that determines how a piece functions as cookware (please see “What should I buy?” for more detail on this). But aside from that, copper metal has inherent dollar value, and thicker copper sheet has always been more expensive and more challenging to work.

Based on my observation of prices on online marketplaces, my experience with different pieces I own, and common sense, here are the breakpoints I see in thickness and collectibility:

  • Least collectible: Less than 1mm
  • Minimally collectible: 1mm to 2mm; less suitable for cooking
  • Moderately collectible: 2mm to 2.5mm; suitable for home cooking
  • Collectible: 2.5mm to 3mm; suitable for professional cooking
  • Highly collectible: 3mm to 4mm; exceptional cooking performance, produced in limited quantities
  • Most collectible: Over 4mm; rarely produced, may be too heavy for home cooking

Counterpoint: Thickness is a lie.

Okay, perhaps “lie” is a strong word here, but let me explain. Measuring the rim of a piece of copper is not necessarily an accurate measurement of its overall mass because many pieces were intentionally manufactured to be thicker in the base than in the sidewalls. Let me introduce the concept of effective thickness: the thickness of the copper in the primary cooking surface of the piece — usually the base and lower sidewalls — that determines how the piece will perform as you cook with it.

20cm and 24cm Gaillard sautésFor example, let’s say a piece measures 2mm at the rim but weighs the same as a piece that is uniformly 3mm thick. How can this be? Where is all that weight? Chances are the pot was intentionally shaped to leave the base and lower sidewalls with thicker copper than the upper sidewalls. Look at the frontispiece of the 1914 Gaillard catalog at right: it shows cutaway views of the pieces that show that the thickness of the copper is thinner in the upper sidewalls. This is highlighted as an advantage: the text running vertically next to the diagrams translates to “Our cookware is manufactured in all thicknesses with proportions that always keep the base stronger.”

In my experience this practice fell away after WWII. I believe Mauviel cookware from the 1970s-1990s was pressed with uniform thickness, which is why I use them reference pieces. I’ve compiled as many of these reference measurements as I can on my reference weights and measures page, and I hope you can use this information to help assess the effective thickness of antique (pre-WWII) pieces.


To me, quality comes down to the unchangeable characteristics of a piece — what it was born with, so to speak. Quality derives from details in the materials and finish of a pan that speak to deliberate choices by its maker to take extra time and expense in its making. The more elements of quality in the piece, the greater its long-term collectibility.

I wrote a post on quality and condition where I go into some detail on this, but here is a summary list of the elements that I believe denote high quality:

  • Three copper rivets for handles on the body of the pan (and two copper rivets per bracket on lid handles)
  • Handle metal appropriate to the type of pan
  • Smooth finishing on cast metal elements
  • On hammered-finish pieces, a consistent hand- or piston-hammered finish (i.e, not embossed)
  • Beveled planes around the base (more common on antique pieces)
  • Base thicker than the sidewalls (more common on antique pieces)

You’ll note that I don’t include thickness as a criteria of quality. This is because coppersmiths produced pieces at a range of thicknesses using the same workmanship. (As above, Gaillard says “Our cookware is manufactured in all thicknesses with proportions that always keep the base stronger.”) While a thicker piece would have been more expensive than a thinner one, they were both made to the same standards of quality.


By condition, I mean the physical state of the piece at the present moment. The great thing about copper cookware is that its condition can often be improved through skillful restoration — but not always.

I invite you again to read my post on quality and condition in which I go into greater detail on how to assess a piece prior to purchase for the condition for these critical factors.

Lining: This is where the nuances between linings that are renewable (tin and silver) versus non-renewable (steel, nickel, and aluminum) come into play. The ability to renew the lining adds to the lifespan of a piece and, in my opinion, enhances its collectibility. While steel, nickel, and aluminum linings are more durable, they cannot be repaired if they are damaged. (The exception is nickel, which I understand can be re-lined with tin!) The most common damage I see on steel-lined pans, for example, is salt pitting across the floor of the pan. Minor pitting is a cosmetic nuisance, but then again, those pits are permanent and unsightly and hurt the pan’s appeal and resale value. By comparison, even the grodiest tin lining can be rendered mirror-bright and perfect again and again for resale, and in my opinion that’s an advantage for a piece’s long-term collectibility.

Geometry: Copper’s malleability renders it liable to bend under force, and the longer a copper pan has been in use the more likely it’s been dropped, whacked, jammed, or otherwise mishandled. Pots can go “out of round” when their sidewalls are compressed and round lids won’t sit neatly on the rim; if the base of the piece is torqued or bowed out, the pot will wobble on a flat surface. Wonky geometry can be addressed by patiently forcing the piece back into the correct alignment with bracing or strategic hammering but the fix is usually not quite perfect. (Steel-, nickel-, and aluminum-lined copper pans are more resistant to geometry problems because the stiff lining reinforces the flexible copper.)

Damage: Serious dents, severe corrosion of the copper, rusted iron handles, separated dovetails, cracks or tears in the copper, uncurling seams, gouges on the floor from knife cuts, over-exuberant polishing that wears away surface features… copper cookware picks up scars from use. If these problems interfere with the pot’s performance and can’t be repaired, then they are impediments to buyers. The death knell is damage that renders a pot non-watertight.

In order to address collectibility, I’d like to add an additional factor for consideration.

58cm diamond saumonièreAccessories: Some pan types were sold with accessories considered important — even essential — to the pan’s function.

  • Lifters: Daubières, braisières, asparagus pans, and fish poaching pans were expected to have removable perforated platforms called lifters. Looking at online listings, unfortunately it seems like the lifter survives with the piece only about half the time. A lifter is not so crucial for a daubière (or similar), but I do think it’s essential for the fish poachers (turbotières, poissonières, et cetera), as delicate fish really do benefit from careful handling during cooking.
  • Potato steamer disk: Mauviel’s odd-shaped potato steamer needs a circular perforated disk to sit in the narrow neck to keep the potatoes from falling into the water reservoir. I consider this a required accessory so if you buy one, make sure the disk is included.
  • Lids: While a lid is nice to have for any piece, it’s essential for a pan dedicated to braising (such as a daubière, braisière, and casserole à glacer) or a liquid cooking pot (stockpot, soup pot, and stewpot). These types of pans were sold with a lid sized and styled appropriately — the handle material of pot and lid should match — and that original lid is very desirable to have. (Lids were optional for fish poaching pans such as turbotières and poissonnières.) Antique pots cut and shaped by hand often had a custom lid made on the spot and if this original lid has vanished it can be quite challenging to find a replacement that will fit correctly, especially in the case of rectangular or oblong daubières and braisières.

I don’t consider tarnish or scratches (what I call “character”) as issues of condition. These are surface phenomena that are easily corrected, and keeping them is a matter of personal preference to the collector.

Here’s how I factor condition into collectibility.

  • Greatest collectibility: Fresh lining; no geometry problems; no damage; original lid and all accessories present
  • Good collectibility: Intact lining; minor geometry problems; original lid or age-appropriate replacement; only missing non-essential accessories
  • Moderate collectibility: Non-renewable lining with cosmetic flaws; missing original lid or with ill-matched replacement; missing essential accessories; noticeable geometry problems and/or early-stage damage halted by restoration
  • Least collectibility: Damaged non-renewable lining; structural damage that renders the pot non-watertight; missing essential accessories; mid- to late-stage damage that can’t be halted or repaired


I use this term to refer to the piece’s apparent history as extrapolated from evidence of its maker or prior owners. In my experience the most reliable indicators of provenance are stamps or recognizable unique elements of craftsmanship.

Provenance enhances collectibility. Copper with a maker’s mark commands a price premium at online marketplaces (to the point where I suspect one seller has counterfeited a simple Gaillard mark in order to increase asking prices for otherwise undistinguished pieces). I have really enjoyed researching and showcasing pieces with royal monograms, restaurant or hotel names, and markings from 19th and early 20th century railway operators. (Look for posts tagged historical interest.)

I’ve spent a great deal of time and effort to research the history of 19th and 20th century coppersmiths in Europe, and I offer this research to you.

Stamps is a gateway to what I have learned about the letters, numbers, and words intentionally pressed into copper. Some stamps are maker’s marks identifying the workshop that made the piece, while others are store stamps or owner’s marks. While a stamp is not always a definitive means to identify a piece’s history — stamps can be added or removed relatively easily — it is still a signpost along the path, so to speak.

My field guides present what I’ve pieced together about several copper makers. Each guide includes examples of stamps I’ve been able to find, as well as my best guess as to the sequence of stamps in use.

Construction is another area of analysis. Coppersmithing evolved dramatically from the 19th to the 20th century, and it’s possible to estimate the time period of a piece based on elements of hand- and machine-craftsmanship. This is not a precise science, as each coppersmith adopted new technology at its own pace, but a holistic examination of the piece should inform your estimate of its age.

Finally, if you would like to do your own research, the Library is where I’ve listed the information resources I’ve used and that might be a good starting point for you. Most notably, I’ve gathered catalogs from various makers — important reference sources for what pieces were available. There are also links to business listings and historical phone books from the online libraries in France, Belgium, and England that have been immensely useful to track the appearance and demise of companies over time.

Provenance doesn’t change a piece’s innate physical characteristics, of course, but evokes a sense of history and can make a piece feel unique. And for me, that is the emotional heart of collecting.

A cautionary tale: The $45,000 windsor

In late 2020 I found a listing on eBay for Antique c1884-88 19th C French Cookware Sauce Pan 6″ Stamped Dehillerin, a nice little unrestored 16cm Windsor carrying an early Dehillerin 18 Rue Coquillière stamp and a buy-it-now price of US$2,500. The seller, a US-based antiques dealer, claimed that the pot had been made and signed by Louis Comfort Tiffany and retailed by Dehillerin. I was immediately curious about this extraordinary provenance. Here is our email correspondence, unedited other than to add a few notes in brackets.

I wrote, “Hi there! I am very curious about this piece. I can’t make out the evidence of Tiffany markings in the photos. How do you know that this piece was made by Tiffany? Thank you!”

The seller replied, “Hi, it signed in several places. One, in particularly, is along the bottom of the circle that contains the E Dehillerin mark. I can add more pics. Can you give me a moment to go through my picture? … Here are som other pics. [See photos below.] I have taken an enormous amount of photos of tho item. If you are looking for a stamped mark that reads anything about Louis Comfort Tiffany, don’t. The mark’s are engraved, etched and overlaid. You’ll need to study and examine closely. Magnification and lighting control will be needed.”


What am I looking for here? I cannot see any words or letters. Can you trace them for me so I can see what you are seeing?

I’ll send some more pics. [The seller did not send any more photos.] Keep in mind. This pan is over 100 years old and has been used to cook. Are you familiar with Louis Comfort Tiffany’s marks and signatures, along with his ensign snowflake, faces and vines? He was affiliated with many companies. Not to be confused with Tiffany Co. Or Tiffany and Sons. Are you a collector?

I am not an expert in Louis Comfort Tiffany, but I am an expert in antique French copper cookware, including Dehillerin. [I did not identify myself as VFC.] I am looking for elements of this pot that are distinct from Dehillerin work of its time. Are you aware of any other copper cookware made by Tiffany?

Then you are aware, E Dehillerin only sold cookware during the period in which this item was made – 1884 to 1889. The products sold wer made by other artists, according to my research. During this same, the Paris Exposition was the phenomenon. The first 1884, the second 1889. LC Tiffany was instrumental in both Expositions and worked with numerous artists. My research shows he did make French cookware. [An extensive chronology of Louis Comfort Tiffany’s life and prolific career in painting, glassmaking, interior design, textiles, ceramics, and other decorative arts does not mention production of cookware.] LC Tiffany was the innovator of all art movements. Question, what is E Dehillerin French cookware made of; whether Sonoma or otherwise?

Yes, I am very familiar with Dehillerin’s early history. How do you know that LC Tiffany was supplying Dehillerin in 1888?

More than once during our communication, you’ve mentioned your knowledge of E Dehillerin and implied your level of expertise. However, you have not substantiated credentials. I have been willing to divulge information gathered from my research coupled with time staking efforts to show intricate, minuscule marks and other identifiers discovered through my examination process. Although, it was easily determined from your first message that there was no intent to purchase the item, I acted accordingly based on the level of confidence with my qualifications, abilities and transferable skills obtained through decades of professional and academic accomplishments; in addition to life experiences, both personal and vicarious. There is not any reason for me to misrepresent the facts presented within the description category of this listing. Particularly because of the procurement source of this item and all of those I offer for consideration to purchase. My only fault is, I have not taken the time to write a description worthy of the item and to upload higher quality of pictures. Both, mere technicalities easily rectified. In refernce to your question relative to artisans who supplied to E Dehillerin during the aforementioned historical period, I ask, how do you know he did not?

My honest advice to you is to withdraw this listing until you can have it professionally authenticated. Your current listing is problematic: the stamp on the piece dates it to 1890 or later based on the documented date of Dehillerin’s purchase of the store on rue Coquillière, so the presence of “1888” on the handle is a serious anachronism. There is no documentation from Dehillerin itself of any collaboration with LC Tiffany, and they would certainly have capitalized on this relationship had it existed. If you assert this piece is LC Tiffany and price it accordingly, you must substantiate these claims. I wish you the best but I urge you to reconsider this representation.

Please edify me. What consideration should be given to any recommendation provided by you? What is your concern? More so. What is your motivation?

It does not sound to me that you are open to accepting any advice. Best of luck with this listing.

You didn’t offer any, other than end the listing. It appears you are not willing to share information relative to E Dehillerin. It’s not a problem. I planned to seek professional advise before our communication. Thanks and good luck to you with whatever you do.

The seller made no changes to the description or photos in the listing. Over the following week the price increased from US$2,500 to $5,000, then to $19,000, and finally to $45,000. A week later the listing was abruptly pulled with the notation that the item was no longer available.


I’m going to go out on a limb here and predict that copper that is (at least theoretically) usable for cooking is more likely to retain collectible value than “shelf queens” destined for display only. I say this because my concept of collectibility requires appeal to a range of prospective buyers, and I think a minority of people are in a position to buy copper just to look at it. I think it’s easier to justify purchasing copper cookware that can return some value in the form of utility.

Set of daily-use Gaillard saucepansIn my opinion, copper that has the greatest sustained usability will be:

  • Sized for home cooking for four to six people
  • Solid-feeling in the hand so you don’t worry about hurting it
  • Thick enough to manage modern cooktop heat (i.e., at least 2mm)
  • Of manageable weight for a normal person to lift and maneuver for cooking and cleaning
  • Equipped with handle metals appropriate to the type of pan (i.e., iron on stick-handled pieces, brass on short-handled pieces)
  • In the conventional shapes ideal for the Western cooking techniques at which copper excels (e.g., saucepans, sauté pans, rondeaux, stewpots, stockpots)

32cm swing-handled high-top daubièreBy comparison, shelf queens are:

  • Too small or too large for routine cooking tasks for the average household (2-6 people)
  • Too thin to handle the heat output of a modern stove or cooktop (i.e., less than 2mm thick)
  • Lightweight and fragile, or conversely, too heavy to be comfortable to lift for cooking and cleaning
  • In unusual shapes not suited for routine cooking (e.g., daubières and fish poachers)


I can’t quantify rarity. By definition, antique and vintage copper refers to prior production, and I don’t think anyone has attempted to count how many pieces of copper there are. In my opinion any piece of European copper made prior to World War II that has survived to the present day is a miracle. I continue to be surprised — and gratified — that we have so many examples of 19th and early 20th century copper readily available for purchase online. Copper made after WWII is a different story because it was mass-produced and imported into the US (where I live) in much greater quantities.

But still. How many pots and pans are out there? I don’t know. All I can tell you is what I think based on what I’ve seen. Here are the real unicorns that I think are worth the investment because I expect they will hold — and improve — their collectibility and value.

  • Consumer-scale (30cm and smaller) pieces in 4mm thickness or better. These are what I’m hunting these days. I have one 28cm Mauviel stewpot that is 4mm so I know they were occasionally made, but they are rarer than hen’s teeth.
  • High-thickness (3.5mm or better) restaurant-scale pieces (32cm diameter and up) with no damage. These kitchen workhorses were usually handled and cleaned pretty roughly and came away with dents, wobbly bases, weakened dovetails, and other relics of hard use that are difficult if not impossible to correct. These pieces have limited appeal due to their size, but their rarity and condition make them exceptional.
  • Modern-era (post-WWII to 1990s) consumer-scale Mauviel sautés at 3.4-3.8mm thickness. For whatever reason, Mauviel was cranking out super-heavy sautés at 28cm, 30cm, and 32cm diameter (the upper range of what I consider home-cook scale) and they are absolutely magnificent — modern-era Mauviel at the top of their game. A lot of these pieces seem to have been exported to the US for light use in home kitchens and they survive in gorgeous shape to this day.
  • Cooking-grade pieces (2.5mm or better) with wrought iron handles. My research suggests that wrought iron was in use only during the early to mid 19th century, before being replaced by more economical cast iron handles. Wrought handles are beautiful — each is hand-shaped and the iron feels smooth and alive. The downside is that they are usually attached to lightweight pieces at 2mm or less that were well-suited to 19th century stoves but are easily overheated on modern cooktops.

You are the only collector who matters.

I mean that. My dad was a car collector and the advice he gave me was “Buy what you love and you won’t care what it cost or what it’s going to be worth.” I think the same thing applies to copper: know yourself and decide what criteria are most important to you. Are you an adventuresome cook? Are you captivated by the beauty of bright polished copper? Are you impressed by the history and character of well-used pieces? Welcome. I hope this page has inspired you to think more deeply about what matters to you, and perhaps also about what might matter to the greater community.

As always, I’d love to hear what you think. I made this into a page — a permanent installation, so to speak — so there isn’t a comment section. But please feel free to contact me with your thoughts.