A porcelain enamel sign is made by fusing a powdered glass colored coating through high heat to an iron substrate. Each powdered glass color is applied and on top of the other and fired until sign design is complete. When this powdered glass has cooled it provides a very durable finish that is almost impervious to the elements.
Made in Mumbai - Fake porcelain signs from India
Originating from India and in some cases China or Australia, these new porcelain signs are often made to deceive the uneducated collector. Most of them are "fantasy" signs, since an original of the same design never existed. Some door pushes and fountain service signs are considered "unmarked reproductions" since they are made to closely resemble an original sign design.
TEN TIPS TO HELP YOU SPOT A FAKE PORCELAIN SIGN
Primarily solid blue or solid green Coca-Cola signs simply never existed. Blue or green were often used as a secondary color, but never the main body of the sign. Coca-Cola red is (and always has been) strictly monitored to maintain an exact appearance. A red colored sign than seems to "off colored" any be a signal that the sign is not authentic.
Fake signs in overall colors that Coca-Cola never used for signage.
When known, compare the position of the original mounting hole positions to the positions on the suspected fake sign. If they are different then, this is usually a signal that the sign may not be authentic. A sign that has no mounting holes is also probably fake, since all signs are attached to either a wall, frame, or hanging bracket in some manner.
Some porcelain Coca-Cola signs used grommets, some did not. Typically grommets should not look new, unless the sign is unused. Old grommets should have the appropriate patina of age and sometimes some chipping and rusting underneath.
ACCURACY OF THE COCA-COLA LOGO
The Coca-Cola logo is and was one of the most closely monitored assets of the Coca-Cola Company. By the 1920's it became very standardized in form and usage. A crudely drawn, out of proportion logo is a major indication that a sign or object is not authentic.
When comparing the two logos, it is obvious that the poorly executed one on the right is from a fake porcelain sign.
Most old authentic signs had a stamp of the manufacturers name and production date located in a discreet area of the image. Some of the newer signs also have a manufacturers name applied to make the sign appear authentic. Remember that simply having an old date on the sign does not mean that the sign it is actually old!
Manufacturer's name stamped in corner of original porcelain sign.
ACCURACY OF THE LETTERING
Coca-Cola signs were made by professionals artists and sign manufacturers, which translates to near perfect. The Coca-Cola company would have allowed no less. Crudely drawn lettering or a lettering font that comes from today's computers was not used.
The top sign is authentic. The bottom sign is a reproduction. Notice the difference in the placement of mounting holes, the difference in type fonts and font colors. Notice the large orange looking rust spot as well.
The top sign is authentic. The bottom image is a reproduction sign showing vertically stretched logo. Also, note that the text under the logo is both computer generated and in the wrong font.
Poor attention to detail in type fonts and font size as well as applying the correct trademark designation for the time period.
LAYERING OF THE ENAMEL
When porcelain signs are manufactured, each color is applied one on top of each other. Each applied color is made to overlap the other colors slightly to allow for any misalignment of the image. This overlap or buildup of enamel is referred to as "shelving". It is usually very noticeable on older signs when held at an angle or running your fingers over the surface. Newer signs don't always have this attribute.
Details showing the texture that is created by the buildup of porcelain layers or "shelving" on an original sign.
The iron substrate used in older signs rusts differently than the newer steel based signs. The newer signs often have an orange powdery looking rust in chipped areas. Old signs that have actually hung outside develop a dark brown or black colored rust that is much different looking than the "new" rust.
Examples of authentic chipping and rust on old porcelain Coca-Cola signs.
An example of newer looking rust that is present on many fake porcelain signs.
The porcelain finish is very durable, but since it is glass based, it also brittle enough to fracture in a shard-like manner when tweaked, bent or hit. Original chips should expose paint layering and have dark brown or black looking rust.
Chips should also be present in areas of use such around the hanging holes or attachment holes. Sometimes edges have been nicked during movement or while the sign rubs against a frame. Be very careful to trust your instincts as to whether the chipping is natural or applied to deceive. Edges are typically chipped in small random spots along the edge where the sign has been nicked by an object. An overall continuous pattern of edge chipping is often cause for concern.
Suspicious edge chipping pattern on a couple of fake porcelain signs.
Modern production methods often produce a rail mark or consistent tracking marks across the porcelain on the back of the sign. The presence of these marks often (but certainly not always) signal the sign as a reproduction. But be aware that some signs after 1950 also have these production marks as well.
Rail and track marks common on the back of recently produced porcelain signs.