The orange glow is caused by whatever was used to produce the red colour.
The green glow in clear glass is caused by the manganese that was used to decolorise the clear glass. Sand often contains iron, which makes clear glass look green (like coke bottles). A glow that is described as "small amount of green glow" or "not really bright" is almost never uranium.
Your ashtray is a standard Murano form and probably made during the 50s/60s, as cheaper chemicals are now used to decolorise clear glass