cast iron

Why Use Cast Iron?

I'm convinced that "non stick" surfaces, such as teflon, are toxic. Newer products come out that sound better, but I cannot help but think that folks just have not yet learned how toxic the new surfaces are. I personally avoid all chemically treated cooking surfaces, aluminum and copper.

Cooking with cast iron helps people get more iron in their diet to build more red blood cells. Doctor's recommend that those with anemia cook with cast iron.

Cast iron can last hundreds of years. Many moderm skillets/griddles last only a few months to a few years.


Cast Iron Cookware in a Nutshell


rough new surface

Take a close look at the cooking surface of this new skillet. It's rough. Apparently, long ago, there were two grades of a cast iron skillet one could purchase. The first is where molten iron is poured into a mold and that's it. The second is where they take the first and machine out the cooking surface to make it much smoother. But that machining process usually doubles the price.

Today's new cast iron cookware is all the first kind. The surface is rough.

side view

This is a closeup of the cast iron skillet showing the original lumpiness of the raw cast iron, followed by layers of seasoning.

I think a person could buy a new cast iron skillet and if used twice a day for six months it would probably be just as good as an old skillet. The most important ingredient would include the use of a stainless steel spatula with a flat edge: as it is used over and over, it will take the "peaks" off as the "valleys" fill with "seasoning"(more on the spatula and the "seasoning" below). It's just that the first few months will have more frustration than if you started off with a great cast iron skillet.

The best idea for a purchase of a cast iron skillet is to buy a Griswold cast iron skillet from ebay.



Here you can see how the griddle surface has been machined to something much smoother. The cast iron cookware offered in stores today doesn't do this. That is just one reason why the really old cast iron cookware is superior.

Old Cast Iron vs. New Cast Iron

Old cast iron and new cast iron are very different beasts.

If discussing skillets, the two characteristics of a pre WW2 pan that first grab your attention are:

The lighter weight means you cook at lower temperature settings on the stove. The smoother surface is a result of the superb iron ore that was found near Lake Erie and also the machining that is no longer done to save on labor expense.

Pictures tell the story better.


On the left is a Lodge 8SK 10.5" skillet. On the right is a Favorite Piqua Ware skillet of the same size. The Lodge is probably 16 years old while the Favorite is at least 74 years old. I don't know the exact date of manufacture for the Favorite but the Favorite factory shut it's doors in late 1934, a casualty of the Great Depression.

Griswolds, Wagners, Wapaks, (and probably others) offered similar quality. Old Lodges were very smooth as well.


The Right Kind of Spatula


It has to be metal. Some people will get concerned that the metal will scratch the surface and ruin the skillet, and their thinking is spot on, but the wacky thing is that in this case, we want it to scratch the skillet. But not just any scratching. We want just the right kind of scratching. Because with just the right kind of scratching, the surface of the skillet will get better and better. Smoother and slicker. Flatter. Bumps of fused on gick will be scraped off and any pits will be slowly filled in with seasoning.

A plastic spatula will not work. At some point something will stick to the skillet. The plastic is not able to scrape it off. And then other little bits will get stuck to the first bit. As time passes, this bump will get bigger and bigger. If a metal spatula were used, the first little bit would not have been more than a few minutes old before it got scraped off. These skillets with the big tumors are going to have to have all the seasoning removed and started over.

Now for a bit of focus on the shape. There is the edge of the spatula that will contact the surface of the skillet, and there are the corners of the spatula that will contact the edge of the skillet.

Removing the Seasoning Layer From Cast Iron

There are three reasons I know of for why you might want to do this:

While I have read of many ways to do this, the technique I have used in the past is to toss it in the coals of a dying fire. I have a stove for wood heat. When the fire gets to the point of being just coals, I toss the cast iron skillet on the top. The next morning I fish it out. All of the crusty or rusty stuff is turned to ash. I brush the ash off with my hand, then dribble a little oil on it and wipe that all over the cast iron with a paper towel. Then I start re-seasoning it.

Oven Cleaned

Some say you can start a cast iron skillet over by using a self cleaning oven. I've also heard some people say they tried this and their skillet cracked.

Here is a cast iron skillet that just finished going for a ride in a self cleaning oven. This skillet had become covered in layers of petrified gunk - both inside and outside the pan. And all that gunk is now ash.

You can also use Oven Cleaner. Just put it in a plastic bag with you Cast Iron. You may have to repeat this process before all the crud is removed.

Begin by spraying the pan with oven cleaner and putting it in a plastic bag for a couple of days. The bag keeps the oven cleaner from drying out so it will continue to work. After a couple of days, remove it from the bag and scrub it in a solution of dish soap/water. I use a brass brush marketed for cleaning white wall tires. It is just the right size for doing pans. If all the burned on grease doesn't come off, repeat the process, concentrating the cleaner to the areas not cleaned.

I DO NOT recommend the following methods of cleaning:


The Recipe for Perfect Cast Iron Seasoning

well seasoned

The basic idea is this: Smear a food-grade drying oil onto a cast iron pan, and then bake it above the oil’s smoke point. This will initiate the release of free radicals and polymerization. The more drying the oil, the harder the polymer. So start with the right oil.

Go to your local health food store or organic grocery and buy a bottle of flaxseed oil. It’s sold as an omega-3 supplement and it’s in the refrigeration section because it goes rancid so easily. Check the expiration date to make sure it’s not already rancid. Buy an organic flaxseed oil. You don’t want to burn toxic chemicals into your cookware to leach out forever more. It’s a fairly expensive oil. I paid $17 for a 17 ounce bottle of cold-pressed, unrefined, organic flaxseed oil. As it says on the bottle, shake it before you use it.

Strip your pan down to the iron using the techniques described above Heat the pan in a 200°F oven to be sure it’s bone dry and to open the pores of the iron a little. Then put it on a paper towel, pour a little flaxseed oil on it (don’t forget to shake the bottle), and rub the oil all over the pan with your hands, making sure to get into every nook and cranny. Your hands and the pan will be nice and oily.

Now rub it all off. Yup – all. All. Rub it off with paper towels or a cotton cloth until it looks like there is nothing left on the surface. There actually is oil left on the surface, it’s just very thin. The pan should look dry, not glistening with oil. Put the pan upside down in a cold oven. Most instructions say to put aluminum foil under it to catch any drips, but if your oil coating is as thin as it should be, there won’t be any drips.

Turn the oven to a baking temperature of 500°F (or as high as your oven goes – mine only goes to 450°F) and let the pan preheat with the oven. When it reaches temperature, set the timer for an hour. After an hour, turn off the oven but do not open the oven door. Let it cool off with the pan inside for two hours, at which point it’s cool enough to handle.

The pan will come out of the oven a little darker, but matte in texture – not the semi-gloss you’re aiming for. It needs more coats. In fact, it needs at least six coats. So again rub on the oil, wipe it off, put it in the cold oven, let it preheat, bake for an hour, and let it cool in the oven for two hours. The picture above was taken after six coats of seasoning. At that point it starts to develop a bit of a sheen and the pan is ready for use.

If you try this, you will be tempted to use a thicker coat of oil to speed up the process. Don’t do it. It just gets you an uneven surface – or worse, baked on drips. Been there, done that. You can’t speed up the process. If you try, you’ll mess up the pan and have to start over.

The reason for the very hot oven is to be sure the temperature is above the oil’s smoke point, and to maximally accelerate the release of free radicals. Unrefined flaxseed oil actually has the lowest smoke point of any oil (see this table). But the higher the temperature the more it will smoke, and that’s good for seasoning (though bad for eating – do not let oils smoke during cooking).

There’s a myth floating around that vegetable oils leave a sticky residue. If the pan comes out of the oven sticky, the cause is one of three things:

It’s possible to use a suboptimal oil for seasoning, like Crisco or bacon drippings, and still end up with a usable pan. Many (most) people do this. But the seasoning will be relatively soft, not as nonstick, and will tend to wear off. If you want the hardest, slickest seasoning possible, use the right oil: flaxseed oil.


Cast Iron Cookware and Tomatoes

Note that tomatoes, tomato sauces and other acidic foods eat away at the seasoning. I would generally avoid cooking these in cast iron.

Cast Iron Cookware and Bacon

Some bacons leave petrified goo on the skillet. This is actually sugar that is used to cure the bacon. The heat causes it to come out and turn into a sort of caramel/candy. Some people call it "bacon brownies." Frying this kind of bacon almost always leads to needing to boil some water in the skillet to get it all out.


Avoid using soap on cast iron cookware




A Brief History Of The Griswold Manufacturing Company Of Erie, Pa, As It Pertains To Collectors Of Cast Iron Cookware

In 1865, two Erie families associated by marriage, joined in a modest venture to manufacture door hinges. The Selden and Griswold union paved the way for The Griswold Manufacturing Company of Erie, Pennsylvania, recognized world wide as producers of fine cast iron products, especially cookware.

Between 1865 and 1957 when they closed production of the plant at the corner of 12th and Raspberry Street, their line of cookware had been sold and used around the world. Their designers and engineers produced many patents spanning almost 100 years of manufacture. Before the turn of the 20th century, they added cast aluminum products to their line. In the 1920's they enameled some cookware and by the 1930's they offered electric items to their product list. They produced commercial pieces for use in restaurants.

The company was in trouble by the 1940's for a variety of reasons. Many products were being introduced by other cookware companies that seemed more attractive to modern cooks. Problems within the company between management and employees widened, the quality of the products seemed to decline, and in 1957 the doors of GMC closed leaving 60+ employees without jobs.

While most of the GMC cookware is a desired collectible, almost all collectors  avoid the small Griswold logo era. The former quality and casting isn't there, for the most part. There seems to be a much larger demand for cast iron, compared to those seeking cast aluminum, enameled, electric, or plated pieces. Eventually, Griswold's strongest competitor, The Wagner Manufacturing Company of Sydney, Ohio, ended up with ownership of their molds. The "double stamped" Wagner/Griswold emblems are not considered important collector's items, nor are the items that say Griswold but were really manufactured in Sydney, Ohio by Wagner.

Some of the overlapping logos produced at the foundry included these:

1865-1883 Selden & Griswold
1865-1909 ERIE or "ERIE"
1874-1905 Spider and Web
1884-1909 Diamond (with ERIE inside the diamond)
1897-1920 Griswold Manufacturing Company (italic lettering, large cross logo)
1919-1940 Griswold Manufacturing Company (block lettering, large cross logo)
1937-1957 Griswold (block lettering, small cross logo)

Some other trademarks include:

Tite Top Dutch Oven
Tite Top Baster
Kwik Bake


Production of cast iron cookware began around 1880 under the ERIE brand.


In 1905 the brand name was changed to Griswold's ERIE and in 1906 the famous Griswold cross logo appeared.

This logo design is known as the Slant/ERIE and it dates from 1906 to 1912.

FYI - Any Griswold piece lacking the word Erie was produced in Wagner's Sidney Ohio plant.


This logo design is known as the Slant/Erie PA U.S.A. (or EPU for short) and it dates from 1909-1929.

no ring

This logo is known as the Block/Erie PA U.S.A. and these date from 1930-1939. Notice the lack of a heat ring that was seen on the older pieces.



This is a Griswold block logo cast iron skillet with heat ring, circa 1920 to 1930. The size is a rare #5 - 7 7/8 x 1 3/4. Marked "5" on the handle and "CAST IRON SKILLET 5 GRISWOLD ERIE, PA., U. S. A. 724 A" on the bottom. There are 15 skillets in this style (block logo w/heat ring) and only 4 sizes are rarer than the #5!

Priced at $594.95.[!brand:Griswold block logo heat ring!][!material:cast iron!][!size:rare #5 skillet!]



The name "Wagner" did not appear on skillets after 1922. When you find one like this #10 shown above you are looking at an old piece. The Sidney, O. stands for Sidney Ohio.

The Wagner Manufacturing Company was founded in Sidney OH in 1891. It became one of the two largest makers of cast iron cookware along with Griswold and continued to be a family owned company until the mid 1950s. After being sold to the Randall Company, Griswold was also acquired in 1957 (you can find pieces with both markings). In the years that followed a series of transactions took place that ended up seeing the Sidney foundry close in 2000.


In a Wagner cast iron skillet, the iron is a little thinner, but it also requires less heat. It might not be widely considered the best cast iron skillet, but it is widely considered to be far better than the "Lodge Logic" stuff found in stores today. Also, a Wagner cast iron skillet usually runs a lot cheaper than Griswold on ebay.



Many people think cast iron is indestructible. It is not. While the build-up of time and the ravages of neglect in the form of carbon and rust, respectively, can be easily cleaned from it, cast iron is in many ways fragile and must be handled with care and respect. Similar to the properties of glass, cast iron is strong but brittle; it will break before it bends.

There are several ways a piece of cast iron cookware can be damaged: chipping, cracking, warping, and pitting. The first two can be caused by physical impact; the second two by improper rapid heating or cooling, also known as thermal shock. Pitting, the result of the chemical erosion of metal, we'll cover in just a minute.

Ironically, chipping and cracking are the least problematic, in that they are only cosmetic-- the pan can still be used without much difficulty. Heat cracks are usually hairline, occuring most often in the sidewall of a pan, and typically either don't leak, or are quickly sealed by seasoning. Collectible value, however, is drastically reduced.

Spotting a chip is usually easy, as they occur primarily on the lip of a pan, or, if the pan has one, the heat ring. Sometimes, what appears to be a chip is actually a void in the casting caused by an air bubble trapped in the iron as it cooled and hardened.

Cracks are often harder if not impossible to detect, unless the pan has been stripped of all built-up seasoning. Even on bare metal, a heat crack is often dismissed as a utensil scratch. Holding the pan at an angle to a bright light source, check any vertical scratches on the sidewall of a pan for a counterpart on the opposite side, noting if it also crosses the rim of the pan. If so, you've got a cracked pan.

Warping can be troublesome. An empty pan placed and left on a burner set on high heat for a very short time can result in warping. With nothing in the pan to absorb and distribute the heat, metal in one spot in the bottom of the pan expands more rapidly than the surrounding area, and what was once smooth and flat ends up irreversibly concave or convex. Rapid cooling, such as dropping a hot pan into a sink full of water, can cause similar damage. The result when trying to use a warped pan is uneven cooking, as liquids and cooking fats now pool in the middle of the warp or are dispersed to the edges of the pan away from it, depending on the direction. Some modern kitchen stoves have also introduced an additional problem using warped cast iron: it doesn't make the necessary flush contact with smooth glass cooktop burners, rendering it all-but-useless on them. A slightly warped pan may still be usable on a gas stove burner or in the oven, but its collectible value is also greatly diminished.

One can easily detect a downward-bowed pan warp. On a hard, level surface, the pan will rock or "wobble", as collectors like to say. By pressing on the rim of the pan at various points, you can feel and see the movement, and listen for the clicking sounds that are tell-tale signs of warping. At the end of the video, you can also see why collectors call such pans "spinners". Note that an upward-bowed pan can still "sit flat" on its perimeter, so checking the surface inside with a straightedge may also be necessary.

Additionally, cosmetic damage can be caused by allowing rust to go unchecked to the point of pitting the metal. Once any significant amount of metal is lost to rust, it cannot be repaired, although, with time and effort, rust pitting in cooking surfaces may be filled in with accumulated layers of new seasoning.

On the bottoms of older pans, you may also see eroded metal that might be mistaken for rust pitting. What you're actually seeing is an acid erosion. Coal, as did natural gas supplies many years ago, contained sulfur as an impurity, which resulted in the formation of sulfuric acid upon burning. Continual use over a sulfur-laden heat source would over time result in metal actually being dissolved and displaced. As a result, finding older pans with no evidence of sulfur pitting is often difficult.

Both forms of metal pitting result in diminished collectible value.

There's another form of damage which results, unfortunately, from good but misguided intentions. You'll often hear or read how simple cast iron cleaning can be if you just burn a pan in a fire. If the fire burns too hot, however, the molecular structure of the iron can be irreparably changed. Iron so-damaged will have an often scaly, patchy,dull red appearance, different from regular rust's orange/brown. Re-seasoning over such damage is usually not possible. A fire-damaged pan:


Although the major foundries produced high quality products, there are sometimes seen instances where defects slipped through the controls. At the time, some common minor defects may have been of no concern to either manufacturer or consumer. Cast iron ware, being considered a rather utilitarian commodity, was commonly shipped in bulk, packed in sawdust in wooden barrels.

Most often seen, and usually mistaken for utensil marks, are pinpoint casting voids. A void is what occurs when the molten iron solidifies without having completely filled the mold cavity. It's like a trapped air bubble. Voids on the cooking surface, if tiny and not numerous, are usually not of concern to the average collector; they will quickly fill with seasoning, and affect neither cooking nor displayability.

More distracting can be a sag. If a part of the sand mold shifted between the time the pattern was removed and the iron was poured, the result would be cast into the molded piece. Sags look like wavy, uneven lines across the surface of the piece. While they don't normally affect usage, their appearance does detract from collectible value.

Wavy lines can also be the result of what's known as a "cold pour". Typically, a foundryman would transfer a ladle from the furnace to the molding area containing enough molten metal to cast several pans at a time. If there was a delay or the molder did not move quickly enough, the metal would begin to cool, impeding it from flowing properly inside the mold of the last of the pans cast. Sometimes, the imperfection would be deemed negligible and not worthy of rejection.

Occasionally, you'll also see characters or other markings that appear shallow or missing altogether. Bear in mind that incised markings on the molded piece would be made by raised areas on the inside surface of the sand mold cavity. If a raised area happened to break off when the pattern was removed, the markings it should have made in the pan would not occur.

Rarely, you will see a piece which appears to have a piece of a foreign object embedded in the iron. This is known as a slag inclusion, and can consist of another metal, or a bit of refractory material from the furnace or the ladle which transferred molten iron to the casting area.


There are a couple of things that you'll regularly see on a cast iron pan that you might mistake for damage or defect. Finish grind marks and flashing are both common, and should not be considered as negatives.

Nearly every cast iron cookware piece produced by the technology of the late 19th century and after will have grinding marks at various points along the outside lip. Under earlier casting technology, the iron entered the mold at what would become the bottom of the pan. With the advent of the woodstove, flat-bottomed pans became necessary, requiring a rethinking of the molding technique. The answer lay in having the iron enter the mold cavity at what would become the outer top edge of the piece, and that's from where the excess iron from the casting process is trimmed. A final pass of the edge across a grinding wheel smoothed any remaining roughness.

Flashing is what occurs when the halves of a sand mold do not come together as precisely as they should. When the iron is poured, some seeps into the tiny crack between the halves, leaving a thin fin or web of metal protruding from the edge of the piece. Most is trimmed off as a part of the finishing process, but some is often seen remaining inside the hanging hole of a pan handle. Most people leave it alone, as it doesn't affect cooking or handling. As long as part of the actual casting is not damaged, the careful trimming or filing off of flashing does not seem to affect collectible value one way or the other.

You'll occasionally see on the bottom of some pieces what appears to be the head of a screw. This is not a repair of a defect, but rather a quality control measure some foundries used after the advent of automation. If a pattern became suspect of causing defective pieces, it would be marked so the pans made from it could be easily identified. A simple method of marking involved driving a screw into the pattern. A curiosity at most, and collectible value is not affected.


There are a few other artifacts of the manufacture of cast iron you'll see from time to time, relating to the processes of pattern-making and molding, that are not necessarily considered damage or defects.

When a change to trademarks or other markings occurred, it was common to alter existing patterns, in order to avoid the expense, time, and trouble of creating entirely new patterns.

One method of pattern alteration involved the creation of a replacement area on a separate thin piece of pattern material. The area containing the obsolete markings would be excised from the existing pattern, and the new piece affixed in its place. If the depth of the area removed did not exactly match the thickness of the replacement piece, its border would be apparent in the resulting castings. Examples of this are often seen on pieces from both Favorite and Chicago Hardware Foundry.

If an area of markings on a piece was to be removed altogether and not replaced, a filler material would simply be applied to the unwanted markings on the pattern, preventing them from being transferred to subsequent molds. If the material was not precisely smoothed to match the surrounding surface on the pattern, the result would show on the casting as an area that appears "smeared". This practice and the manifestation of it on a cast iron piece is sometimes referred to as "buttering". While not a defect per se, such pieces are somewhat less desirable as collectibles.




Heat Ring, Smoke ring (or fire ring). Some skillets have a rim that runs the entire circumference on the bottom. This rim kept the heated surface slightly elevated above the heat source. It is usually abbreviated in reference as HR or SR. Whether it has a heat ring or not can be a huge difference in the value of the piece.

Smooth bottom (as opposed to HR above). Skillets without heat rings are referred to as smooth bottom skillets. They lack that rim going around the entire circumference on the bottom of the skillet.

Pattern number (or PN) Griswold Manufacturing Company wasn’t always very consistent with their identification of pieces; nevertheless, many of their cookware pieces were identified with both a size and a pattern number. An example would be a number 8 trivet for a Dutch oven, with PN 206. Many muffin pans can be identified as Griswold by pattern number only. On occasion, a Letter or small number might accompany the size or PN. These seem to indicate a run series, and generally can be ignored.

Extra finished or Plated. When the cast iron products were coated with an outer finish of nickel or chromium, they were extra finished. The finish was both dull and polished.

Hammered. Metal that was deliberately dimpled in manufacture is hammered. Hammered products are tougher to locate than regular items.

Hinged. When a lid and bottom were hooked together as a set, it is referred to as hinged.

Examples would be found among skillet/lids; dutch oven/lids, and even waffle irons/bases.

Porcelain or enamel finish. Starting in the 20’s, Griswold began to produce some porcelain or enamel finished items in four colors: turquoise blue, canary yellow, jade green and mandarin red. They seemed to coat just the outside of skillets and lids in the porcelain while the inside remains black iron. In the 30’s, they changed colors and expanded their porcelainizing to a variety of cookware styles, like covered casseroles, fish boats, even individual dutch service ovens with lids. These newer colors were usually two toned, like red with cream or yellow with gray. All of the porcelain items tend to bubble in manufacture causing pinholes in the finish or to chip and stain from use. It’s hard to find them in mint condition.

Gate Marks

Sand casting has existed for many hundreds of years. The basic technique of sand casting iron cookware has changed little over time. The foundry pours molten iron into a mold created in sand to create a piece in a particular design. The mold is created by packing sand, very artfully, around a pattern, often made of wood. When this pattern is removed from the sand it creates the area to be filled with iron in the exact shape of the wooden model. It is in this void the molten iron flows. Amazing detail can be achieved by a skilled artisan. Binders are used mixed in the sand to make the mold hold together long enough for the founder to pour and serves to hold precise detail in the sand. There are many formulas for binders often with clay as a component. Minor changes in the casting process can show us the approximate date of a piece. The oldest pieces will have a circular "sprue" mark on the underside of the piece. This technique was used until the mid-to late 1700's. Most pieces were cast upside down, to avoid having an unsightly sprue or gate marks on the top of the piece. The sprue is the point where the foundryman poured the molten iron into the mold. It is a sort of pipeline for the metal to flow into the mold itself. Any piece that is cast, even those today, will have at least one point where you can see where the iron entered the mold. Sometimes it is well ground and polished down but you can still find it most of the time. If the cast iron has a "gate mark", it is older than 1900. Gate marks happened when the pan was broken out of the mold. Between 1875 and 1900, they were phased out by injecting the mold at the lip of the pan instead of the bottom.