A ghost mark is a faint impression that is barely visible on a piece of vintage cast iron cookware.

Notice the faint ‘Miami’ logo at the top of the skillet.

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In order to understand how a ghost mark occurs, lets talk about how cast iron cookware is manufactured:

Cast iron cookware is created using a process called ‘sand mold casting’.

First, you start with a pattern. The pattern is what the finished product will look like (size, logos, handles) and can be made of wood, metal, or plastic. It can be used over and over to make many molds.

Removing the imprinted pattern for outer one half of a small pot

The mold is composed of a damp sand mixture tightly packed around the pattern. The pattern is designed to be removed to create a cavity where molten iron will be poured. Molds typically consist of 2 to 3 separable layers that create a box.

Placing imprinted pattern around a sand shaped pot

Pushing together both sides of the pot

Placing top cover with a passage way for molten iron to be poured.

Iron needs to heat to 2800 degrees Fahrenheit to become molten.

Molten iron being poured into the mold

The next step is to wait for the iron to cool and solidify. Once solidified, the hardened sand is broken away to reveal the final product.

Final product — small cast iron pot

Now, lets talk about the ghost marks. Over time, companies evolved and came up with new logo designs to replace the old. Instead of starting from scratch, they modified old patterns by filling them in and then adding the new pattern over the top.

A number 6 Sidney Hollow Ware piece with an ‘Erie’ ghost mark.

Over time, after many new patterned molds were used to make new logo skillets, the material used to fill in the old patterns eroded away. This allowed the old logos to ‘bleed through’, causing what is referred to as a ghost mark.

A long griddle with a “Wagner” ghost mark.

To view full YouTube video on how to create a small cast iron pot, visit https://youtu.be/XcxDY7vQnPo