Transitional marbles are among the earliest American-made marbles. The term 'transitional' applies to most slag-type marbles that have one pontil. These marbles were probably made by one of several processes. Some were made by gathering a glob of molten glass from a pot onto the end of a punty and then either rounding a single marble off the end or allowing the glass to drip off the end of the punty into a machine as another worker cut the stream to create individual globs of glass. It is also likely that some later transitionals were actually made completely by machine. In this case, the stream of glass came out of a furnace, through a shearing mechanism, and then went into a crude set of rollers that rounded the marbles, but did not rotate them around all axes. As a result, the cut-off mark from the shearing mechanism remained.
The marbles are collectively called 'transitional' because many were made partly by hand and partly by machine. Thus, they represent a bridge between handmade marbles and machine-made marbles.
Several American companies produced transitional marbles. Most of the companies were short lived. Among the more well known companies are Navarre Glass Company and M. F. Christensen & Son Company. It is very difficult to identify individual transitional marbles with specific companies. This is because very, very few have ever been found in their original packaging.
Transitional marbles are usually identified by the type of pontil. Some are also identified by the manufacturer, but this can be difficult, at best.
Regular pontil transitionals have a pontil on one end that looks just like the pontil on a handmade marble. This type is fairly rare. It is likely that many of these were not even made using any type of machine. Rather, they were individually hand-gathered on a punty and then rounded in a device and sheared off.
Ground pontil transitionals have a pontil on one end that has been ground and faceted. Many of these are Regular pontil transitionals that the manufacturer took the time to grind the pontil off of.
Melted pontil transitionals are more common than either regular pontils or ground pontils. These are marbles that have a pontil on one end that has been partially melted into the marble. The pontil was either melted manually over a flame or else was melted into the marble surface while the marble was being formed in the early marble-making machine. Most Melted pontil transitionals exhibit either a '9 and swirl pattern' or else a looping pattern where the white runs in a band or bands from the pole, over the top of the marble, and back to the pole. It is generally believed that the '9' pattern was made by the M. F. Christensen & Son Company and that the looping pattern was made by the Navarre Glass Company. However, since the glass for these marbles was hand-gathered, it may very well be that they were simply made by different gatherers in the same factory. The '9' pattern marbles (marbles where the white glass on the top pole forms a '9') seem to be a little more common than the loop pattern marbles.
Pinpoint pontil marbles are very rare. Occasionally, melted pontil transitionals or crease pontil transitionals are confused with pinpoint pontil transitionals. The pontil on these marbles is characterized by a very tiny pontil that looks almost like the head of a pin. The pontil on these marbles was formed because the glass was a little too cool when it was sheared off the punty and dripped into the machine. As a result, the cut-off spot did not completely melt into the marble because the marble cooled too quickly as it was forming. These pontils are very rare. Occasionally, they are found on marbles that are made from two opaque colors of glass, rather than a transparent and opaque color.
Fold pontil transitionals are also rarer than Melted pontils. The pontil is characterized by a tiny finger of glass that is folded over at the cut-off point and partially melted into the marble surface. This pontil is formed by a similar process to the Pinpoint pontil. The glass was a little too cool when it was sheared off into the machine. As a result, the cut-off spot did not completely melt into the marble because the marble cooled too quickly as it was forming.
Crease pontil transitionals are fairly common. It is not known whether these were made by the M. F. Christensen & Son Company or the Akro Agate Company. There has been speculation by some that they were also made in Japan. These marbles are characterized by a spidery crease line that runs along the entire bottom of the marble. Again, the mark was formed because the glass was too cool when it was sheared off as it was dripping into the marble-making machinery. These marbles tend to be transparent blue, aqua, green or brown, with a bright opaque white swirls in and on them. They are also found in opaque white with a transparent color spiral.
Pinch pontil transitionals are also fairly common. These have been found in transparent color with white spirals and in opaque white with transparent color spirals, just like the crease pontils. However, where the crease pontil transitionals have a haphazard swirl to them, the pinch pontils have a nicely controlled spiral similar to an M. F. Christensen '9' pattern. Many of the colors resemble Christensen Agate Company colors, leading some collectors to believe that these are very early Christensen Agate. They are probably American and not Japanese.