This is a late 19th century covered butter dish in the Early American Pressed Glass (EAPG) category of opalescent Vaseline, or sometimes called opalescent Canary glass, with an enameled decoration. The maker is Northwood. The date is circa 1897 and most of the company's production was circa 1897 to 1898.
Sometimes Alaska gets confused with Klondyke, another pattern based on the Alaskan Gold Rush by Northwood and produced during the same years.
The bottom of the butter dish is 6 5/8" by 6 5/8" by 1 ½". To the top of the finial the height is 5".
There is a chip on one side of the finial. If the dish was in perfect condition, the 2002 price guide value for this covered butter dish is $450. I list this piece to my shop for a buyer who might need the bottom, or who doesn't care that the finial has the chip. I point to the chip with red arrows in close-up photos.
The enameled decoration is around the lower sides of the cover, small blue flowers with yellow middles, pale leaves, and large white leaves. There is a line of gold trim above the enameled decoration.
The covered butter dish is one dish in a set of four that Northwood termed a "Table Set."
There are no other chips, nicks or cracks, just the internal glass marks due to the glassmaking process.