Fenton No. 5172 Swan Candlestick in Amethyst Carnival
Fenton introduced their No. 6 Swan candleholder back in the 1930s after acquiring the molds from the Diamond Glass-ware Company. They were reissued in 1971 as No. 5172 as part of their "Original Formula Carnival" line using a modified mold adding additional detail to the upper stem and candle cup.
They measure about 6 1/2 inches high and have a base diameter of 3 1/4 inches
Reference The Glass Candlestick Book, Felt/Stoer, Volume 1, page 199.