Detecting Stein Repairs*

by Gary Kirsner

Recognizing the condition of a beer stein is as important as knowing the basic value of the stein. Being able to identify damage and repairs on steins you are buying will frequently prevent you from buying at a price that does not properly reflect the stein’s value. Defects that occur on beer steins can be divided into the following categories:

• Body damage;
• Body repair;
• Pewter damage;
• Pewter repair;
• Factory defect.

Detection of repairs that might be found on porcelain, stoneware, earthenware and other ceramic materials will be the primary focus of this article. The identification of unrepaired damage and the comparison to factory defects will also be discussed.

There are five primary ways to detect repairs:

• Visual inspection;
• Touch inspection;
• Scratch application;
• Chemical application;
• Black light.

Each of these methods has strengths and weaknesses.

Visual Inspection

Careful examination of a stein will frequently result in the visual observation that something is repaired or damaged. Cracks, hairlines, flakes and chips are relatively easy to detect with a visual observation. It is much more difficult to detect repairs, especially if the quality of the repair work is very good. An examination should be made by following a set pattern of closely viewing each section of the stein.

Signs of possible repair include an unusual variation in the color of the glaze, an indication of an uneven ridge or indentation, or paint peeling. The most frequently recognizable repair is when a white glazed area on the inside of a stein has been painted over and the color has turned to a pinkish or yellowish shade. Of course, not everything that looks like it might be a repair is actually a repair. It will usually be necessary to use an additional type of inspection or test to determine if a repair exists.

Touch Inspection

A touch inspection will usually be all that is required to accompany the visual inspection to determine the presence or lack of repairs. A repaired area on a stein will usually feel somewhat different than the original surface. The reason for this is that the original surface has been fired at a high temperature, creating a virtual bonding of the glaze or colors to the body of the stein. In contrast, a repaired surface is unfired paint that has been applied to the surface of the stein. The original surface will always feel harder than the (softer) repaired surface. Some people will describe the difference between the original and repaired surfaces as being colder versus warmer. Should an area that looked suspicious also feel different than other areas of the stein, a repair might be present but further verification could be required. There are three methods that require specific equipment in order to verify the presence of a repair.

Scratch Application

All repaired surfaces are softer than the original fired surfaces and therefore will scratch with considerably less pressure than the original surfaces. The best tools to use for this test are a sharp pin or a very small knife with a pointed blade. It should be obvious that scratching a repair will damage it. Therefore, if this test is to be done, a careful non-defacing technique should be used. The very slow pressing of a pin or pointed knife blade into a repaired area will result in a very slight impression on the surface. An original, unrepaired surface would not show any trace of an impression.

Some steins are nearly invulnerable to damage as the result of scratching the original surface. Others may scratch if sufficient pressure is applied. Mettlach steins and stoneware steins tend to be very resistant to scratching while porcelain steins can easily be scratched. Please keep this in mind when using a scratch test for repairs. It is also good policy not to scratch a stein you do not own without permission from the owner. Always ask before doing anything that might damage a stein (or the repair on a stein).

Chemical Application

One test that absolutely identifies a repair involves the application of chemicals. When applied to a repaired surface, paint strippers (purchased in a hardware store) will absolutely prove the presence or lack of a repair. Of course this will also result in the destruction of what might have been a very good repair. I generally use this method only to prove that a repair does not exist. Chemicals that are weaker than paint strippers can also be used (e.g., acetone or turpentine). I do not recommend using chemicals, as they can be flammable and toxic. They are dangerous to use without taking proper precautions.

Black Light

A method that was very popular at one time involves the application of a black (ultra-violet) light to the surface of the stein. This needs to be done in the dark. The surface area will glow differently if a repair is present — sometimes. What actually occurs is that the presence of lead or some other mineral impurities will result in a different glow on the surface of the stein at the location of a repair. While this worked well twenty years ago, modern paints do not contain lead and therefore will rarely light up with a black light. This is probably the least reliable method for detecting repairs.

Factory Defects

Not all defects present on a stein can be described as damage. In fact, nearly every stein has some factory flaws. These flaws can include firing lines, flakes, chips, glaze runs, glaze omissions and bubbles. While most factory flaws do not affect the value of the stein, there can be confusion in trying to differentiate a factory flaw from damage that occurred after the stein left the factory.

Determining the difference between a factory flaw and after-factory damage is usually fairly simple. One rule that will apply to most factory damage, as opposed to non-factory damage, is that any damage occurring in the factory will have factory-applied and fired glaze covering the damage. It is very common to find small chips or flakes on steins. These usually occur around the base area, on decorative bands, or on the handle. Even the relatively high quality standards that Villeroy & Boch followed in producing their steins at Mettlach did not come close to eliminating factory flaws. A simple scratch test, or if absolutely necessary, a chemical test, will always prove whether an apparent flake or chip that appears to be covered with glaze is in fact a factory flaw rather than after-factory damage.

Differentiating hairline cracks or even large cracks from glaze crazing and factory firing lines can sometimes be more difficult. Obviously large cracks penetrate through the body of the stein. Water will easily pass through such a crack. While this is obviously non-factory damage, hairline cracks need closer examination. A non-factory hairline crack will be very tight. The water test will not work, or it could take several days, but a close examination that reveals a line on the inside and the outside in the same location is an indication of a non-factory hairline crack.

Crazing in the glaze generally found on the inside of steins will usually be a non-uniform pattern of lines covering a small portion of the surface, but perhaps as much as the entire surface. These lines penetrate no greater than the depth of the glaze and they do not indicate a damage that occurred after leaving the factory. Rather, they indicate a discoloration of the surface of the glaze that generally has no effect or only a minimal effect on the value of the stein. Note that it is usually possible to clean the surface in order to remove the crazing, or at least the obvious indication that crazing is present because dirt has settled into the crazed area.

Firing lines appear on steins produced by many manufacturers, but are most noted for their presence on Mettlach steins. These firing lines are usually found in the etched area on the bodies of Mettlach steins, but sometimes they are found on glazed bands, inlays and even the upper and lower rims. The distinction between a firing line and an after-factory crack can sometimes be made by the presence of factory glaze. Glaze will be present whenever the firing line occurs in areas where glaze was applied, such as the upper rim or glazed bands. When firing lines occur in etched areas that have a matte finish, the lines will usually be short and zigzagged. These lines will usually be black or at least dark and, most importantly, they only penetrate the outer layer. There should never be a corresponding line visible on the inside of the stein.


*Reprinted from The Beer Stein Journal, May 1995, by permission from Gary Kirsner Auctions.