Thanks for the pictures.
Diamond Glass made the Victory pattern from 1928 until they closed in 1931. Since it was only produced for three years, it is not as plentiful on the market as some other glass.
Based on my research, if it is in perfect condition, the current retail (replacement or insurance) value of your plate is approximately $75. If you were to sell it, you could expect to get the fair market (private sale or auction) value of approximately 40% of the retail amount or $30, depending on location and actual condition.
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