From the collecrtion of long standing mysteries, here is a pressed glass charger standing on 4 feet. The inside is mottled dark red, at the rim a yellow (silver nitrate?) colour applied and brushed off.
http://tinypic.com/ftegc6.jpgThe underside is mottled dark moss green toward mottled light blue. The base colour of the glass is impossible to tell - I think it's opaque black.
http://tinypic.com/ftegqu.jpgI've only ever seen one before - but that was no more than 6" and the seller had no clue what it was or where it came from. The charger is 12" (31cm) in diameter, the height is 2 3/4" (7cm)
Tips and hints re pattern/ mould, colour techniques, age etc. are welcome - be bold, dare to speculate! Nobody is going to correct you anyway.
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