Master Marble, Master Glass
Master Marble Company, Clarksburg, WV 1930 - 1941.
Master Glass, Bridgeport, WV 1941 -1974.
Master Glass basically being a reorganization of Master Marble Company, using the same brand of machinery, along with using old packaging stock, has created difficulty in identifying one, from the other.
The same brand of machinery also employed by Akro Agate leaves us with additional confusion in regard to their similar Patch style marbles, though Master's earlier machined cut off system created a more acute 'V' shaped cutline, and more often, cutlines pointing in opposite directions.
Along with the multitude of patch variations produced by both Master Marble and Master Glass, Master Marble additionally produced Swirls and Moss Agates, and the later Master Glass, additionally produced Sunburst and Cat's Eye marbles.
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