M.F. Christensen marble identification help.

According to Www.marblecollecting.com The M.F. Christensen & Son Company operated in Akron, Ohio, from1904 until 1917. Martin Christensen patented the first marble-making machine.

Many M.F. Christensen marbles have shear marks or cut-lines on them, from the marble making process. M.F. Christensen machines did not have automatic feed systems. The molten glass had to be hand- fed into the machinery.M.F. Christensen marbles are strictly single-stream marbles. They are either single-color opaque or two-color slag or swirl. This is because the glass for a particular batch was all mixed in one furnace pot and not the separate streams used by later manufacturers.

Interestingly, there do not appear to be any M.F. Christensen & Son Company marbles that exhibit a distinctive set of three colors. The company seems to have confined itself to marbles of only one or two color.

Company marbles are Slags.

These marbles have a swirling pattern of transparent colored base with opaque white swirls. M.F. Christensen & Son Company slags are easily identified by the “9” pattern on the top pole and the “cut-off line” on the bottom. These patterns are caused by the twisting motion used in hand gathering the glass out of the furnace and keeping the glass on the end of the punty as a stream of it was allowed to drip into the machine.

The marbles are found in blue, green, brown, purple, red, orange, aqua, yellow, and clear. M.F. Christensen slags are found in a wide array of shades of each of the colors mentioned. The brown and purple are the most common, perhaps they were the easiest or cheapest to make. The blue and green are next most common, and are fairly easy to find. Clear and aqua are more difficult. Occasionally, the aqua marbles will have a little bit of oxblood in them. Red is more difficult. Yellow is the second hardest to find and “true” orange is the most difficult color to find. Generally, the better defined the “9”, the more valuable the marble. Also, the brighter and clearer the base transparent color, the more highly valued is the marble. Some of these marbles are truly beautiful.

The value for slags varies greatly depending on the craftsmanship exhibited in the “9” and the rarity of the hue of the color. There is a wide variation in hues, even within one color, of M.F. Christensen slags. This variation is much more pronounced than you see in other manufacturers. It is not known if this was intentional, or the result of the company’s inability to accurately replicate color formulas. "

According to www.marblealan.com SLAGS

Most M.F. Christensen marbles seem to have been slags, which are easily identified as having originated from this company because they normally have a "nine and tail" which was formed when the glass was twisted from the furnace. Opposite the "nine" a cut-off line can often be seen, too. As mentioned, earlier examples may have single pontils, which were typically melted in the finishing process. Slags were called National Onyx by the company and were available in such colors as amber, purple, blue, green, clear, aqua, yellow, orange, and lavender, in approximate increasing order of rarity. This company did not produce red slags as earlier thought. Very dark blue slags were coined "Royal Blues." Some slags were produced in very large (over 1 1/2") sizes.

Some National Onyxes, which are probably early types, are referred to as "horizontal slags." These are easily recognized, as instead of having a single "nine" swirl the white spirals multiple times around the marble, forming a tight corkscrew pattern. These are valued much more highly than regular slags.